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Physics 101 Mechanics
October 2021
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Physics 101 Mechanics
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October 5, 2021
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October 5 of 2021
What is the typical mass of a 5-foot , 6 in tall woman , in kilograms
When angular velocity changes with respect to time then? (a) an angular acceleration is produced (b) a linear acceleration is produced (c) it constitute a couple (d) a linear velocity is produced
A can filled with water is revolved in a vertical circle of radius 4 metre and the water does not fall down. The time period of revolution will be (a) 4 sec (b) 10 sec (c) 8 sec (d) 1 sec
A coin kept on a rotating gramophone disc just begins to slip if its centre is at a distance of 8 cm from the centre of the disc. The angular velocity of the gramophone disc is then doubled. Through what distance, the coin should be shifted towards the centre, so that the coin will just…
When a body P moves on a circular path, the centripetal acceleration is (a) directed inwards from P, to the centre of the circle (b) directed tangential to the circumference of the circle, at P (c) directed perpendicular to the planc of the circle, at P (d) directed outward, perpendicular…
A body is traveling in a circle at constant speed. It (a) has an inward acceleration (b) has constant velocity. (c) has no acceleration (d) has an outward radial acceleration
A body makes a displacement of 4 m due East from a point O and then makes displacement of 3 m due North. Its resultant displacement from O (a) 7 m (b) 1 m (c) 5 m (d) 1 . 2 m
A small body attached at the end of an inextensible string completes a vertical circle, then its (a) angular momentum remains constant (b) linear momentum remains constant (c) angular velocity remains constant (d) total mechanical energy remains constant
The angular velocity depends upon the rate of change of the? (a) Angular acceleration (b) Angular Distance. (c) Angular Displacement. (d) torque
The displacement in metres of a body varies with time t in second as y = t2 – t – 2. The displacement is zero for a positive of t equal to (a) 1 s (b) 2 s (c) 3 s (d) 4 s
Which one of the following is the unit of velocity? (a) kilogram (b) metre (c) m/s (d) second
A body starts from rest and travels with uniform acceleration a to make a displacement of 6 m. If its velocity after making the displacement is 6 m/s, then its uniform acceleration a is (a) 6 m/s² (b) 2 m/s² (c) 3 m/s² (d) 4 m/s²
The dimensional formula for acceleration is (a) [LT2] (b) [LT?2] (c) [L2T] (d) [L2T2]
A boy moves on a circular distance of radius R. Starting from a point A he moves to a point B which is on the other end of the diameter AB. The ratio of the distance travelled to the displacement made by him is (a) ?/2 (b) ? (c) 2? (d) 4?
A body starts from rest and travels for five seconds to make a displacement of 25 m if it has travelled the distance with uniform acceleration a then a is (a) 3 m/s² (b) 4 m/s² (c) 2 m/s² (d) 1 m/s²
A body starts from rest and travels with an acceleration of 2 m/s². After t seconds its velocity is 10 m/s. Then t is (a) 10 s (b) 5 s (c) 20 s (d) 6 s
A body starts from rest and travels with uniform acceleration of 2 m/s². If its velocity is v after making a displacement of 9 m, then v is (a) 8 m/s (b) 6 m/s (c) 10 m/s (d) 4 m/s
A body starts from rest. If it travels with an acceleration of 2 m/s², its displacement at the end of 3 seconds is (a) 9 m (b) 12 m (c) 16 m (d) 10 m
A boy starts from a point A, travels to a point B at a distance of 1.5 km and returns to A. If he takes one hour to do so, his average velocity is (a) 3 km/h (b) zero (c) 1.5 km/h (d) 2 km/h
The dimensional formula for velocity is (a) [LT] (b) [LT-1] (c) [L2T] (d) [L-1T]
The dimensional formula for speed is (a) T-1 (b) LT-1 (c) L-1T-1 (d) L-1T
A body starts from rest and travels for t second with uniform acceleration of 2 m/s². If the displacement made by it is 16 m, the time of travel t is (a) 4 s (b) 3 s (c) 6 s (d) 8 s
Which one of the following is the unit of velocity? (a) kilogram (b) metre (c) m/s (d) second
A body starts from rest and travels with uniform acceleration on a straight line. If its velocity after making a displacement of 32 m is 8 m/s, its acceleration is (a) 1 m/s² (b) 2 m/s² (c) 3 m/s² (d) 4 m/s²
A boy starts from a point A, travels to a point B at a distance of 1.5 km and returns to A. If he takes one hour to do so, his average velocity is (a) 3 km/h (b) zero (c) 1.5 km/h (d) 2 km/h
A boy starts from a point A, travels to a point B at a distance of 3 km from A and returns to A. If he takes two hours to do so, his speed is (a) 3 km/h (b) zero (c) 2 km/h (d) 1.5 km/h
The displacement in metres of a body varies with time t in second as y = t2 – t – 2. The displacement is zero for a positive of t equal to (a) 1 s (b) 2 s (c) 3 s (d) 4 s
An airplane flying horizontally with a speed of 500 km/h at a height of 800 m drops a crate of supplies (see the following figure). If the parachute fails to open, how far in front of the release point does the crate hit the ground?
The rms value of the electric field of the light coming from the sun is 720 N/C. The average total energy density of the electromagnetic wave is- (1) 4.58 × 10–6 J/m3 (2) 6.37 × 10–9 J/m3 (3) 81.35 × 10–12 J/m3 (4) 3.3 × 10–3 J/m3
Which of the following are not electromagnetic waves ? [AIEEE–2002] (1) Cosmic-rays (2) gamma-rays (3) beta-rays (4) X-rays
The nature of electromagnetic wave is – (1) longitudinal (2) longitudinal stationary (3) transverse (4) transverse stationary
Select wrong statement from the following for EMW - (1) are transverse (2) travel with same speed in all medium (3) travel with the speed of light (4) are produced by accelerating charge
The AM range of radiowaves have frequency – (1) less than 30 MHz (2) more than 30 MHz (3) less than 20000Hz (4) more than 20000Hz
The frequency from 3 to 30 MHz is known as – (1) audio band (2) medium frequency band (3) very high frequency band (4) high frequency band
The frequency from 3 × 109 Hz to 3 × 1010 Hz is – (1) high frequency band (2) super high frequency band (3) ultra high frequency band (4) very high frequency band
The ozone layer is earth's atmosphere is crucial for human survival because it – (1) has ions (2) reflects radio signals (3) reflects ultraviolet rays (4) reflects infra red rays
In which part of earth's atmosphere is the ozone layer present ? (1) troposphere (2) stratosphere (3) ionosphere (4) meosphere
If E ? and B ? are the electric and magnetic field vectors of electromagnetic waves then the direction of propagation of electromagnetic wave is along the direction of – 1) E ? (2) B ? (3) E ? × B ? (4) none of these
An electomagnetic radiation has an energy 14.4 KeV. To which region of electromagnetic spectum does it belong ?
A T.V. tower has a height of 100 m. How much population is covered by T.V. broadcast, if the average population density around the tower is 1000/km2 ?
The electromagnetic waves do not transport -
In an electromagnetic wave the average energy density is associated with
In an electromagnetic wave the average energy density associated with magnetic field will be
In an electomagnetic wave, the amplitude of electric field is I V/m. The frequency of wave is 5 × 1014 Hz. The wave is propagating along z-axis. The average energy density of electric field, in Joule/m3 , will be
The area to be covered for T.V. telecast is doubled, then the height of transmitting antenna (T.V. tower) will have to be –
What should be the height of transmitting antenna if the T.V. telecast is to cover a radius of 128 km ?
A point source of electromagnetic radiation has an average power output of 800W. The maximum value of electric field at a distance 3.5 m from the source will be –
A point source of electromagnetic radiation has an average power output of 800W. The maximum value of electric field at a distance 3.5 m from the source will be – In the above problem, the maximum value of magnetic field will be –
In a plane electomagnetic wave, the electric field oscillates sinusoidally at a frequency of 2 × 1010 Hz and amplitude 48 V/m. The amplitude of oscillating magnetic field will be – In the above problem, the wavelength of the wave will be –
In a plane electomagnetic wave, the electric field oscillates sinusoidally at a frequency of 2 × 1010 Hz and amplitude 48 V/m. The amplitude of oscillating magnetic field will be –
A bolt drops from the ceiling of a moving train car that is accelerating northward at a rate of 3.10 m/s2.
A passenger walks from one side of a ferry to the other as it approaches a dock.Passenger's velocity is 1.60 m/s due north relative to the ferry, and 4.50 m/s at an angle of 30.0 ? west of north relative to the water.
What is the tangenial velocity of a train moving in circular track with radius of 9.72 m if its centripetal acceleration is 37 m/s^2?
A 2-kg hammer strikes a 1.5-gram nail for it to move 1-cm. What is the work done on the hammer by the nail and what is the average force exerted on the nail by the hammer?
A person exerts a horizontal force of 190 N in the test apparatus shown in the drawing. Find the horizontal force M (magnitude and direction) that his flexor muscle exerts on his forearm.
Why does NO2 dimerise?
. Balls are thrown vertically upward in such a way that the next ball is thrown when the previous one is at the maximum height. If the maximum height is 5m, the number of balls thrown per minute will be (A) 40 (B) 50 (C) 60 (D) 120
A particle is projected vertically upwards from a point A on the ground. It takes t1 time to reach a point B but it still continues to move up. If it takes further t2 time to reach the ground from point B then height of point B from the ground is (A) 1/2 g (t1 + t2)^2 (B) g t1 t2 (C) 1/8 g (t1…
A ball is thrown vertically down with velocity of 5m/s. With what velocity should another ball be thrown down after 2 seconds so that it can hit the 1st ball in 2 seconds (A) 40 m/s (B) 55 m/s (C) 15 m/s (D) 25 m/s
3. A particle starts moving rectilinearly at time t = 0 such that its velocity ‘v’ changes with time ‘t’ according to the equation v = t2 – t where t is in seconds and v is in m/s. The time interval for which the particle retards is (A) t < 1/2 (B) 1/2 < t < 1 (C) t > 1 (D) t < 1/2 and…
12. A force F = Be^–Ct acts on a particle whose mass is m and whose velocity is 0 at t = 0. It’s terminal velocity (velocity after a long time) is : (A) C mB (B) B mC (C) BC m (D) – B mC
0. A body moves with velocity v = lnx m/s where x is its position. The net force acting on body is zero at . (A) 0 m (B) x = e2m (C) x = em (D) x = 1 m
9. The co-ordinates of a moving particle at a time t, are given by, x = 5 sin 10 t, y = 5 cos 10 t. The speed of the particle is - (A) 25 (B) 50 (C) 10 (D) None
A body starts from rest and is uniformly accelerated for 30 s. The distance travelled in the first 10s is x1 , next 10 s is x2 and the last 10 s is x3 . Then x1 : x2 : x3 is the same as (A) 1 : 2 : 4 (B) 1 : 2 : 5 (C) 1 : 3 : 5 (D) 1 : 3 : 9
A particle has a velocity u towards east at t = 0. Its acceleration is towards west and is constant, Let xA and xB be the magnitude of displacements in the first 10 seconds and the next 10 seconds. (A) xA < xB (B) xA = xB (C) xA > xB (D) the information is insufficient to…
The displacement of a body is given by 2s = gt2 where g is a constant. The velocity of the body at any time t is (A) gt (B) gt/2 (C) gt2/2 (D) gt3/3
A car runs at constant speed on a circular track of radius 100 m taking 62.8 s on each lap. What is the average speed and average velocity on each complete lap ? (A) velocity 10 m/s speed 10 m/s (B) velocity zero, speed 10 m/s (C) velocity zero, speed zero (D) velocity 10 m/s, speed zero
A body covers first 1/3 part of its journey with a velocity of 2 m/s, next 1/3 part with a velocity of 3 m/s and rest of the journey with a velocity 6m/s. The average velocity of the body will be (A) 3 m/s (B) 11/3 m/s (C) 8/3 m/s (D) 4/3 m/s
A car travels from A to B at a speed of 20 km h–1m and returns at a speed of 30 km h–1. The average speed of the car for the whole journey is (A) 5 km h–1 (B) 24 km h–1 (C) 25 km h–1(D) 50 km h–1
. A hall has the dimensions 10m × 10m × 10 m. A fly starting at one corner ends up at a diagonally opposite corner. The magnitude of its displacement is nearly (A) 5 root 3 m (B) 10 root 3 m (C) 20 root 3 m (D) 30 root 3 m
Is the acceleration of a projectile equal to zero when it reaches the top of its trajectory? If not, why not?
. Give an example from your own experience in which the velocity of an object is zero for just an instant of time, but its acceleration is not zero.
1. At which point on its path a projectile has the smallest speed?
An antelope is being pulled by two forces whose vector-component expressions are: F1=4Ni+(-9.3Nj)+(-5.4Nk) F2=4.7Ni+9.1Nj+(-9.8Nk) What is the angle in degrees between these two vectors?
An antelope is being pulled by two forces whose vector-component expressions are: F1=4Ni+(-9.3Nj)+(-5.4Nk) F2=4.7Ni+9.1Nj+(-9.8Nk)
What are the dimensions of lenth in force × displacement/time (A) –2 (B) 0 (C) 2 (D) none of these
One watt-hour is equivalent to (A) 6.3 × 103 Joule (B) 6.3 × 10–7 Joule (C) 3.6 × 103 Joule (D) 3.6 × 10–3 Joule
If the unit of length is micrometer and the unit of time is microsecond, the unit of velcoity will be : (A) 100 m/s (B) 10 m/s (C) micrometers (D) m/s
The unit of impulse is the same as that of : (A) moment force (B) linear momentum (C) rate of change of linear momentum (D) force
The SI unit of the universal gas constant R is : (A) erg K–1 mol–1 (B) watt K–1 mol–1 (C) newton K–1 mol–1 (D) joule K–1 mol
Which of the following system of units is NOT based on the unit of mass, length and time alone (A) FPS (B) SI (C) CGS (D) MKS
Which of the following is not the unit of time (A) solar day (B) parallactic second (C) leap year (D) lunar month
Light year is the unit of (A) speed (B) mass (C) distance (D) time (C) mass, time and velocity (D) length, time and mass
Which of the following is not the name of a physical quantity ? (A) kilogram (B) impulse (C) energy (D) density (C) mass, time and velocity (D) length, time and mass
1. Which of the following sets cannot enter into the list of fundamental quantities in any system of units ? (A) length, mass and velocity (B) length, time and velocity (C) mass, time and velocity (D) length, time and mass
convert ethanol to ethene by dehydration of alcohol show mechanism
A train accelerates from 36 km/h to 54 km/h in 10 sec. Find Acceleration assume uniform acceleration
When angular velocity changes with respect to time then? (a) an angular acceleration is produced (b) a linear acceleration is produced (c) it constitute a couple (d) a linear velocity is produced
A can filled with water is revolved in a vertical circle of radius 4 metre and the water does not fall down. The time period of revolution will be (a) 4 sec (b) 10 sec (c) 8 sec (d) 1 sec
A coin kept on a rotating gramophone disc just begins to slip if its centre is at a distance of 8 cm from the centre of the disc. The angular velocity of the gramophone disc is then doubled. Through what distance, the coin should be shifted towards the centre, so that the coin will just…
When a body P moves on a circular path, the centripetal acceleration is (a) directed inwards from P, to the centre of the circle (b) directed tangential to the circumference of the circle, at P (c) directed perpendicular to the planc of the circle, at P (d) directed outward, perpendicular…
A body is traveling in a circle at constant speed. It (a) has an inward acceleration (b) has constant velocity. (c) has no acceleration (d) has an outward radial acceleration
A body makes a displacement of 4 m due East from a point O and then makes displacement of 3 m due North. Its resultant displacement from O (a) 7 m (b) 1 m (c) 5 m (d) 1 . 2 m
A small body attached at the end of an inextensible string completes a vertical circle, then its (a) angular momentum remains constant (b) linear momentum remains constant (c) angular velocity remains constant (d) total mechanical energy remains constant
The angular velocity depends upon the rate of change of the? (a) Angular acceleration (b) Angular Distance. (c) Angular Displacement. (d) torque
The displacement in metres of a body varies with time t in second as y = t2 – t – 2. The displacement is zero for a positive of t equal to (a) 1 s (b) 2 s (c) 3 s (d) 4 s
Which one of the following is the unit of velocity? (a) kilogram (b) metre (c) m/s (d) second
A body starts from rest and travels with uniform acceleration a to make a displacement of 6 m. If its velocity after making the displacement is 6 m/s, then its uniform acceleration a is (a) 6 m/s² (b) 2 m/s² (c) 3 m/s² (d) 4 m/s²
The dimensional formula for acceleration is (a) [LT2] (b) [LT?2] (c) [L2T] (d) [L2T2]
A boy moves on a circular distance of radius R. Starting from a point A he moves to a point B which is on the other end of the diameter AB. The ratio of the distance travelled to the displacement made by him is (a) ?/2 (b) ? (c) 2? (d) 4?
A body starts from rest and travels for five seconds to make a displacement of 25 m if it has travelled the distance with uniform acceleration a then a is (a) 3 m/s² (b) 4 m/s² (c) 2 m/s² (d) 1 m/s²
A body starts from rest and travels with an acceleration of 2 m/s². After t seconds its velocity is 10 m/s. Then t is (a) 10 s (b) 5 s (c) 20 s (d) 6 s
A body starts from rest and travels with uniform acceleration of 2 m/s². If its velocity is v after making a displacement of 9 m, then v is (a) 8 m/s (b) 6 m/s (c) 10 m/s (d) 4 m/s
A body starts from rest. If it travels with an acceleration of 2 m/s², its displacement at the end of 3 seconds is (a) 9 m (b) 12 m (c) 16 m (d) 10 m
A boy starts from a point A, travels to a point B at a distance of 1.5 km and returns to A. If he takes one hour to do so, his average velocity is (a) 3 km/h (b) zero (c) 1.5 km/h (d) 2 km/h
The dimensional formula for velocity is (a) [LT] (b) [LT-1] (c) [L2T] (d) [L-1T]
The dimensional formula for speed is (a) T-1 (b) LT-1 (c) L-1T-1 (d) L-1T
A body starts from rest and travels for t second with uniform acceleration of 2 m/s². If the displacement made by it is 16 m, the time of travel t is (a) 4 s (b) 3 s (c) 6 s (d) 8 s
Which one of the following is the unit of velocity? (a) kilogram (b) metre (c) m/s (d) second
A body starts from rest and travels with uniform acceleration on a straight line. If its velocity after making a displacement of 32 m is 8 m/s, its acceleration is (a) 1 m/s² (b) 2 m/s² (c) 3 m/s² (d) 4 m/s²
A boy starts from a point A, travels to a point B at a distance of 1.5 km and returns to A. If he takes one hour to do so, his average velocity is (a) 3 km/h (b) zero (c) 1.5 km/h (d) 2 km/h
A boy starts from a point A, travels to a point B at a distance of 3 km from A and returns to A. If he takes two hours to do so, his speed is (a) 3 km/h (b) zero (c) 2 km/h (d) 1.5 km/h
The displacement in metres of a body varies with time t in second as y = t2 – t – 2. The displacement is zero for a positive of t equal to (a) 1 s (b) 2 s (c) 3 s (d) 4 s
The rms value of the electric field of the light coming from the sun is 720 N/C. The average total energy density of the electromagnetic wave is- (1) 4.58 × 10–6 J/m3 (2) 6.37 × 10–9 J/m3 (3) 81.35 × 10–12 J/m3 (4) 3.3 × 10–3 J/m3
Which of the following are not electromagnetic waves ? [AIEEE–2002] (1) Cosmic-rays (2) gamma-rays (3) beta-rays (4) X-rays
The nature of electromagnetic wave is – (1) longitudinal (2) longitudinal stationary (3) transverse (4) transverse stationary
Select wrong statement from the following for EMW - (1) are transverse (2) travel with same speed in all medium (3) travel with the speed of light (4) are produced by accelerating charge
The AM range of radiowaves have frequency – (1) less than 30 MHz (2) more than 30 MHz (3) less than 20000Hz (4) more than 20000Hz
The frequency from 3 to 30 MHz is known as – (1) audio band (2) medium frequency band (3) very high frequency band (4) high frequency band
The frequency from 3 × 109 Hz to 3 × 1010 Hz is – (1) high frequency band (2) super high frequency band (3) ultra high frequency band (4) very high frequency band
The ozone layer is earth's atmosphere is crucial for human survival because it – (1) has ions (2) reflects radio signals (3) reflects ultraviolet rays (4) reflects infra red rays
In which part of earth's atmosphere is the ozone layer present ? (1) troposphere (2) stratosphere (3) ionosphere (4) meosphere
If E ? and B ? are the electric and magnetic field vectors of electromagnetic waves then the direction of propagation of electromagnetic wave is along the direction of – 1) E ? (2) B ? (3) E ? × B ? (4) none of these
An electomagnetic radiation has an energy 14.4 KeV. To which region of electromagnetic spectum does it belong ?
A T.V. tower has a height of 100 m. How much population is covered by T.V. broadcast, if the average population density around the tower is 1000/km2 ?
The electromagnetic waves do not transport -
In an electromagnetic wave the average energy density is associated with
In an electromagnetic wave the average energy density associated with magnetic field will be
In an electomagnetic wave, the amplitude of electric field is I V/m. The frequency of wave is 5 × 1014 Hz. The wave is propagating along z-axis. The average energy density of electric field, in Joule/m3 , will be
The area to be covered for T.V. telecast is doubled, then the height of transmitting antenna (T.V. tower) will have to be –
What should be the height of transmitting antenna if the T.V. telecast is to cover a radius of 128 km ?
A point source of electromagnetic radiation has an average power output of 800W. The maximum value of electric field at a distance 3.5 m from the source will be –
A point source of electromagnetic radiation has an average power output of 800W. The maximum value of electric field at a distance 3.5 m from the source will be – In the above problem, the maximum value of magnetic field will be –
In a plane electomagnetic wave, the electric field oscillates sinusoidally at a frequency of 2 × 1010 Hz and amplitude 48 V/m. The amplitude of oscillating magnetic field will be – In the above problem, the wavelength of the wave will be –
In a plane electomagnetic wave, the electric field oscillates sinusoidally at a frequency of 2 × 1010 Hz and amplitude 48 V/m. The amplitude of oscillating magnetic field will be –
A bolt drops from the ceiling of a moving train car that is accelerating northward at a rate of 3.10 m/s2.
A passenger walks from one side of a ferry to the other as it approaches a dock.Passenger's velocity is 1.60 m/s due north relative to the ferry, and 4.50 m/s at an angle of 30.0 ? west of north relative to the water.
What is the tangenial velocity of a train moving in circular track with radius of 9.72 m if its centripetal acceleration is 37 m/s^2?
A 2-kg hammer strikes a 1.5-gram nail for it to move 1-cm. What is the work done on the hammer by the nail and what is the average force exerted on the nail by the hammer?
A person exerts a horizontal force of 190 N in the test apparatus shown in the drawing. Find the horizontal force M (magnitude and direction) that his flexor muscle exerts on his forearm.
Why does NO2 dimerise?
. Balls are thrown vertically upward in such a way that the next ball is thrown when the previous one is at the maximum height. If the maximum height is 5m, the number of balls thrown per minute will be (A) 40 (B) 50 (C) 60 (D) 120
A particle is projected vertically upwards from a point A on the ground. It takes t1 time to reach a point B but it still continues to move up. If it takes further t2 time to reach the ground from point B then height of point B from the ground is (A) 1/2 g (t1 + t2)^2 (B) g t1 t2 (C) 1/8 g (t1…
A ball is thrown vertically down with velocity of 5m/s. With what velocity should another ball be thrown down after 2 seconds so that it can hit the 1st ball in 2 seconds (A) 40 m/s (B) 55 m/s (C) 15 m/s (D) 25 m/s
3. A particle starts moving rectilinearly at time t = 0 such that its velocity ‘v’ changes with time ‘t’ according to the equation v = t2 – t where t is in seconds and v is in m/s. The time interval for which the particle retards is (A) t < 1/2 (B) 1/2 < t < 1 (C) t > 1 (D) t < 1/2 and…
12. A force F = Be^–Ct acts on a particle whose mass is m and whose velocity is 0 at t = 0. It’s terminal velocity (velocity after a long time) is : (A) C mB (B) B mC (C) BC m (D) – B mC
0. A body moves with velocity v = lnx m/s where x is its position. The net force acting on body is zero at . (A) 0 m (B) x = e2m (C) x = em (D) x = 1 m
9. The co-ordinates of a moving particle at a time t, are given by, x = 5 sin 10 t, y = 5 cos 10 t. The speed of the particle is - (A) 25 (B) 50 (C) 10 (D) None
A body starts from rest and is uniformly accelerated for 30 s. The distance travelled in the first 10s is x1 , next 10 s is x2 and the last 10 s is x3 . Then x1 : x2 : x3 is the same as (A) 1 : 2 : 4 (B) 1 : 2 : 5 (C) 1 : 3 : 5 (D) 1 : 3 : 9
A particle has a velocity u towards east at t = 0. Its acceleration is towards west and is constant, Let xA and xB be the magnitude of displacements in the first 10 seconds and the next 10 seconds. (A) xA < xB (B) xA = xB (C) xA > xB (D) the information is insufficient to…
The displacement of a body is given by 2s = gt2 where g is a constant. The velocity of the body at any time t is (A) gt (B) gt/2 (C) gt2/2 (D) gt3/3
A car runs at constant speed on a circular track of radius 100 m taking 62.8 s on each lap. What is the average speed and average velocity on each complete lap ? (A) velocity 10 m/s speed 10 m/s (B) velocity zero, speed 10 m/s (C) velocity zero, speed zero (D) velocity 10 m/s, speed zero
A body covers first 1/3 part of its journey with a velocity of 2 m/s, next 1/3 part with a velocity of 3 m/s and rest of the journey with a velocity 6m/s. The average velocity of the body will be (A) 3 m/s (B) 11/3 m/s (C) 8/3 m/s (D) 4/3 m/s
A car travels from A to B at a speed of 20 km h–1m and returns at a speed of 30 km h–1. The average speed of the car for the whole journey is (A) 5 km h–1 (B) 24 km h–1 (C) 25 km h–1(D) 50 km h–1
. A hall has the dimensions 10m × 10m × 10 m. A fly starting at one corner ends up at a diagonally opposite corner. The magnitude of its displacement is nearly (A) 5 root 3 m (B) 10 root 3 m (C) 20 root 3 m (D) 30 root 3 m
Is the acceleration of a projectile equal to zero when it reaches the top of its trajectory? If not, why not?
. Give an example from your own experience in which the velocity of an object is zero for just an instant of time, but its acceleration is not zero.
1. At which point on its path a projectile has the smallest speed?
What are the dimensions of lenth in force × displacement/time (A) –2 (B) 0 (C) 2 (D) none of these
One watt-hour is equivalent to (A) 6.3 × 103 Joule (B) 6.3 × 10–7 Joule (C) 3.6 × 103 Joule (D) 3.6 × 10–3 Joule
If the unit of length is micrometer and the unit of time is microsecond, the unit of velcoity will be : (A) 100 m/s (B) 10 m/s (C) micrometers (D) m/s
The unit of impulse is the same as that of : (A) moment force (B) linear momentum (C) rate of change of linear momentum (D) force
The SI unit of the universal gas constant R is : (A) erg K–1 mol–1 (B) watt K–1 mol–1 (C) newton K–1 mol–1 (D) joule K–1 mol
Which of the following system of units is NOT based on the unit of mass, length and time alone (A) FPS (B) SI (C) CGS (D) MKS
Light year is the unit of (A) speed (B) mass (C) distance (D) time (C) mass, time and velocity (D) length, time and mass
Which of the following is not the name of a physical quantity ? (A) kilogram (B) impulse (C) energy (D) density (C) mass, time and velocity (D) length, time and mass
1. Which of the following sets cannot enter into the list of fundamental quantities in any system of units ? (A) length, mass and velocity (B) length, time and velocity (C) mass, time and velocity (D) length, time and mass
convert ethanol to ethene by dehydration of alcohol show mechanism
A train accelerates from 36 km/h to 54 km/h in 10 sec. Find Acceleration assume uniform acceleration