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Physics 101 Mechanics
December 2021
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Physics 101 Mechanics
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December 7, 2021
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December 7 of 2021
When a spring is stretched by 5 cm, its elastic potential energy is 1 J. What will its elastic potential energy be if it is compressed by 10 cm?
The temperature of the walls in a room is significant determinant of comfort; a quick calculation can show why. (The calculation is a bit artificial, but the point is clear.) A human has about 1.8 m2 of skin. If a person is unclothed in dry air of 24°C, the skin will be about 33°C. SupposeâŠ
Jason, a 60 kg cyclist, is pedaling his bike at a good clip, using a total energy of 400 W. As he exercises, his body will start to warm up, and he will perspire to keep himself cool. A. Assuming Jasonâs pedaling has a typical 25% efficiency, by how much would his body temperature riseâŠ
To blow up a rubber balloon, you need to provide a gauge pressure of about 2000 Pa. Suppose you inflate a spherical balloon from a diameter of 10 cm to a diameter of 30 cm. Assume normal atmospheric pressure at sea level. What is the change in volume of the balloon? How much work do you doâŠ
Your lungs have a volume of approximately 4.0 L. While visiting the seaside on a chilly 10ÂșC day, you quickly take a deep breath, all your lungs can hold. The air quickly heats up to your body temperature of 37ÂșC. Assume that you hold the volume of your lungs constant, and that the numberâŠ
. A ball of mass 2kg hangs from a 4 m long string. If the string is raised to an angle of 30o above the vertical axis and then released. 2.1 What is the velocity of the ball as it passes its lowest point of motion? 2.2 What is its acceleration upon reaching its maximum distance on the otherâŠ
A ship sails from seawater into fresh water, and in the process, sink slightly. Upon removing 4.8 Ă105 kg of the shipload is removed, the ship retains the level it had before entering fresh water. What was the mass of the ship before part of the load was removed?
A 2-kg block oscillates on the end of a spring with a spring constant of 100 N/m. The oscillation is started by elongating the spring 10 cm from its equilibrium position, then giving the block a speed of 2 m/s. What is the amplitude of oscillation?
The maximum velocity and acceleration of a harmonic oscillator are given as v_max and a_max, respectively. The period of oscillation in terms of v_max and a_max is
deep-sea diver experiences a 9.73Ă105 Pa pressure increase as he dives from the sea level to its floor. 4.1 From the sea level, how deep is the floor? 4.2 What is the absolute pressure at a half-way point to the depth of the sea?
A baryon is produce in a certain reaction with a kinetic energy of 3642 MeV
A 2-in steel plate and 2-in cast iron plate are compressed with one Âœ in-13 UNC grade 8 bolts and nut. One Âœ N American Standard washer is used under the head of the bolt, and another identical washer is used under the nut. An external load of 14 kips is applied to the entire joint. âŠ
. A solid plastic sphere of radius 10 cm has charge with uniform density throughout its volume. The electric field 5 cm from the center is 86 kN/C radially inward. Find the magnitude of the electric field 15cm from the center. (Answer: 76.4KN/C)
A 2-in steel plate and 2-in cast iron plate are compressed with one Âœ in-13 UNC grade 8 bolts and nut. One Âœ N American Standard washer is used under the head of the bolt, and another identical washer is used under the nut. An external load of 14 kips is applied to the entire joint. a)âŠ
A heat pipe for an electronics application uses water as the working fluid. The evaporator, condenser, and adiabatic lengths are 3 cm each. The diameter of the vapor space is 5 mm, and the wicking structure consists of 3 layers of #400 mesh 304 stainless steel screen (wire diameter = 0.00098âŠ
Consider Ammonia (NH3) film boiling in a Porous bed via Fukusako et al. (1986) as follows Determine and plot qmin vs. porosity 0.1 <? < 0.9 in increments of ??=0.1 for NH3 at boiling conditions Tboil=-33.321°C. Assume the packed bed has D = 100 mm, H = 100 mm and use the NIST web siteâŠ
A heavy block is suspended from a vertical spring. The elastic potential energy is stored in the spring is 0.8 J. What is the elongation of the spring if the spring constant is 100 N/m
Air and water at 70 ?F flow in a vertical pipe of diameter D=0.98 inches at rate of mair ? =31.3?10-3 slugs/sec and mwater ? =0.583?10-3 slug/sec, respectively. The exit pressure is 14.7 psia, and the pressure 18 inches upstream is 15.0 psia. Use the Martinelli-Lockhart correlationâŠ
3. A nuclear reactor has cylindrical cooling passages 0.20 inches in diameter and 4 feet long. Water at 680 psia and 400 ?F enters the tube at a velocity of 20 ft/sec and the heat flux is uniform along the length, qâ =q/A= 700,000 BTU/hr-ft^2. Determine / sketch the wall temperatureâŠ
are viewing. So what we have is a condenser that's operating at a pressure 0.95 TSC. We have 144 tubes in a 12 by 12 square array, which have an inner diameter of one inch in an outer diameter of 1.2 inches. It is desired that the steam be condensed at a rate of ÂŁ6800 mass per hour and theâŠ
A body starts moving a velocity of 3m/s and moves in a straight-line motion with uniform acceleration. After 5 seconds of time, it gained the velocity of 5.5 m/s. fine uniform acceleration and the distanced travelled in 10 seconds.
You ran and made 2 laps around a 400m track. What were your average speed and average velocity if you ran for 200 seconds?
3. A man drops a ball off a cliff. If it is travelling 40m/s just before it hits the ground, how tall is the cliff? (a=9.81m/s^2).
the pressure of helium gas is initially 35 atmospheres after many balloons been blown up,the pressure has decreased to 5 atmospheres.what fraction of the original gas remains in the cylinder
determine the magnitude of the vector sum
Briefly explain the conceptual model of effective computer based instruction for adult, outling the three units (output, process and input
Suppose you are sitting, naked, on a steel bench with a temperature of 10°C. The only thing insulating the core of your body (temperature 37°C) is a layer of skin (the epidermis and dermis together are about 4 mm thick) and fat (varies from individual to individual, but a typical thicknessâŠ
The temperature of the walls in a room is significant determinant of comfort; a quick calculation can show why. (The calculation is a bit artificial, but the point is clear.) A human has about 1.8 m2 of skin. If a person is unclothed in dry air of 24°C, the skin will be about 33°C. SupposeâŠ
If you get a cup of coffee in a paper cup, you may be given a corrugated paper sleeve to put around it to make it comfortable to hold. Explain the purpose of the paper sleeve, and how it accomplishes this. Why is the paper sleeve corrugated?
Jason, a 60 kg cyclist, is pedaling his bike at a good clip, using a total energy of 400 W. As he exercises, his body will start to warm up, and he will perspire to keep himself cool. A. Assuming Jasonâs pedaling has a typical 25% efficiency, by how much would his body temperature riseâŠ
On a hot summer day, a cup of flavored shaved ice can be a welcome treat. Suppose you ignore the obvious âbrain freezeâ danger and eat an 8 oz (0.22 kg) cup of ice rather quickly. When it melts in your stomach, how much will this reduce your body temperature? How much heat is needed to meltâŠ
In the United States, railroad cars ride on steel rails. Until the mid-1900s, most track consisted of 11.9 m lengths connected with expansion joints that allow for the rails to expand and contract with temperature. If a section of rail is exactly 11.900 m long on a hot, sunny day when it warmsâŠ
Your lungs have a volume of approximately 4.0 L. While visiting the seaside on a chilly 10ÂșC day, you quickly take a deep breath, all your lungs can hold. The air quickly heats up to your body temperature of 37ÂșC. Assume that you hold the volume of your lungs constant, and that the numberâŠ
A child attending a carnival in a quaint seaside town has been given a spherical helium balloon that is 30 cm in diameter. How many moles of helium does the balloon contain? She âwants to keep the balloon fresh,â so she puts in the freezer, cooling it down from the hot 28°C outside âŠ
A child has been given a helium balloon. Ignoring repeated parental suggestions of tying it to his wrist, he lets it go so that it rapidly rises into the sky. As the balloon rises, it expands, because the pressure of the atmosphere decreases. Ignoring heat exchanges with the atmosphere (aâŠ
What are the rms speeds of a nitrogen molecule (mass ? 10?26 kg) at the following temperatures? Room temperature of 68ÂșF (20ÂșC) The coldest temperature ever observed on earth, ?129ÂșF (?89ÂșC) Polar night on Mars, ?133ÂșC The coldest temperature achieved in the laboratory, 0.5 nK
If 50g of ice at -10 degrees Celsius is added to 300 cm ^ 3 of water at 25 degrees Celsius in a 100g Al calorimeter. What is the final temperature, in degrees Celsius?
A lamp consumes 1000 J of electrical energy in 10 s. Calculate its power.
Calculate the kinetic energy of a body of mass 2 kg moving with a velocity of 0.1 m/s.
How much work should be done on an object of mass 120 kg to increase its velocity from 25 m/s to 40 m/s?
Calculate the power of an electric motor that can lift 800 kg of water ti store in a tank at a height of 1500 cm in 20 s.(g=10 m/s^2)
Calculate the force of gravitation between two objects of masses 50 kg and 120 kg respectively, kept at a distance of 10 m from each other. (G=6.673 x 10^-11 kg m/s
A body of mass 500 g is at rest on a frictionless surface. Calculate the distance travelled by it in 10 s when acted upon by a force of 10^-2 N.
It is required to increase the velocity of a scooter of mass 80 kg from 5 m/s to 25 m/s in 2 seconds. Calculate the force required.
When a force of 40N is applied on a body, it moves with an acceleration of 5 m/s^2. Calculate the mass of the body.
When a missile is fired from a tank, it gets a momentum of 2000 Kg m/s. If the velocity of the missile is 50 m/s, calculate the mass of the missile.
A 2 kg metal block at 50 degrees Celsius is placed in contact with another 1 kg piece of the same metal at 20 degrees Celsius. What will be the final temperature of both?
How much heat of energy is needed to convert 10 kg of water at 50 degrees C into water vapor at 120 degrees C?
Silver's melting point is 960 degrees Celsius and its specific heat is 0.056 cal / g. Its heat of fusion is 21.1 cal / g.
A 50g piece of metal is heated to 200 degrees Celsius and dropped into a plastic cup containing 0.4 kg of 20 degrees Celsius water. If the thermal equilibrium is established at 22.4 degrees Celsius, find the specific heat of the metal in Kcal / kg degrees Celsius.
A 100g mass copper calorimeter contains 150g of water and 8g of ice in thermal equilibrium at atmospheric pressure. 100g of lead at 200 degrees Celsius are introduced into the calorimeter. Find the final temperature, in degrees Celsius, if there is no release of heat to the environment.
A 2.0 kg block of aluminum has an initial temperature of 10 degrees C. If 140 kJ of heat is added to the block, what is the final temperature, in degrees Celsius?
A student heats a 10 g iron nail (specific heat of 464 J/(kg C) ) with a flame. The nail is then put into 100 g of water at 10 C. The water temperature rose to 20 C, what was the initial temperature of the nail?(specific heat of water is 4186 J/(kg C) )
150 kcal of heat increases the temperature of 2 kg of material to 400 degrees F. What is the specific heat of the material in Kcal / kg x degrees C?
05. Pure tones of 2, 6, and 12 Hz are played near a taut string, and only the 12Hz tone causes the string to vibrate in one of its modes; from this information what are the possible LNRF of the string? a. 3Hz b. 4Hz c. 6Hz d. 12Hz e. more than one of the above
angular kinematics and torque
3. Hallar la ecuaciĂłn dimensional de "s" en la siguiente fĂłrmula fĂsica. \[ \frac{V^{2} A}{T}=-s a+Q \] \( V= \) Velocidad; \( A= \) ĂĄrea; \( T= \) tiempo; \( \mathrm{a}= \) aceleraciĂłn a) \( L^{2} T^{2} \) b) LT d) \( L^{3} T^{-1} \) e) \( L^{-3} T \) c) \( L^{3} T \)
The partial pressure of ether ????1 over a solution of acetone in ether at 30°C is 0.713 bar at a mole fraction of acetone, ????2 =0.200. The partial pressure of acetone ????2 at this same concentration is 0.120 bar. Given that the partial pressures for the pure components are ????2?âŠ
When a spring is stretched by 5 cm, its elastic potential energy is 1 J. What will its elastic potential energy be if it is compressed by 10 cm?
The temperature of the walls in a room is significant determinant of comfort; a quick calculation can show why. (The calculation is a bit artificial, but the point is clear.) A human has about 1.8 m2 of skin. If a person is unclothed in dry air of 24°C, the skin will be about 33°C. SupposeâŠ
Jason, a 60 kg cyclist, is pedaling his bike at a good clip, using a total energy of 400 W. As he exercises, his body will start to warm up, and he will perspire to keep himself cool. A. Assuming Jasonâs pedaling has a typical 25% efficiency, by how much would his body temperature riseâŠ
To blow up a rubber balloon, you need to provide a gauge pressure of about 2000 Pa. Suppose you inflate a spherical balloon from a diameter of 10 cm to a diameter of 30 cm. Assume normal atmospheric pressure at sea level. What is the change in volume of the balloon? How much work do you doâŠ
Your lungs have a volume of approximately 4.0 L. While visiting the seaside on a chilly 10ÂșC day, you quickly take a deep breath, all your lungs can hold. The air quickly heats up to your body temperature of 37ÂșC. Assume that you hold the volume of your lungs constant, and that the numberâŠ
. A ball of mass 2kg hangs from a 4 m long string. If the string is raised to an angle of 30o above the vertical axis and then released. 2.1 What is the velocity of the ball as it passes its lowest point of motion? 2.2 What is its acceleration upon reaching its maximum distance on the otherâŠ
A ship sails from seawater into fresh water, and in the process, sink slightly. Upon removing 4.8 Ă105 kg of the shipload is removed, the ship retains the level it had before entering fresh water. What was the mass of the ship before part of the load was removed?
A 2-kg block oscillates on the end of a spring with a spring constant of 100 N/m. The oscillation is started by elongating the spring 10 cm from its equilibrium position, then giving the block a speed of 2 m/s. What is the amplitude of oscillation?
The maximum velocity and acceleration of a harmonic oscillator are given as v_max and a_max, respectively. The period of oscillation in terms of v_max and a_max is
A baryon is produce in a certain reaction with a kinetic energy of 3642 MeV
. A solid plastic sphere of radius 10 cm has charge with uniform density throughout its volume. The electric field 5 cm from the center is 86 kN/C radially inward. Find the magnitude of the electric field 15cm from the center. (Answer: 76.4KN/C)
A heat pipe for an electronics application uses water as the working fluid. The evaporator, condenser, and adiabatic lengths are 3 cm each. The diameter of the vapor space is 5 mm, and the wicking structure consists of 3 layers of #400 mesh 304 stainless steel screen (wire diameter = 0.00098âŠ
A heavy block is suspended from a vertical spring. The elastic potential energy is stored in the spring is 0.8 J. What is the elongation of the spring if the spring constant is 100 N/m
Air and water at 70 ?F flow in a vertical pipe of diameter D=0.98 inches at rate of mair ? =31.3?10-3 slugs/sec and mwater ? =0.583?10-3 slug/sec, respectively. The exit pressure is 14.7 psia, and the pressure 18 inches upstream is 15.0 psia. Use the Martinelli-Lockhart correlationâŠ
3. A nuclear reactor has cylindrical cooling passages 0.20 inches in diameter and 4 feet long. Water at 680 psia and 400 ?F enters the tube at a velocity of 20 ft/sec and the heat flux is uniform along the length, qâ =q/A= 700,000 BTU/hr-ft^2. Determine / sketch the wall temperatureâŠ
are viewing. So what we have is a condenser that's operating at a pressure 0.95 TSC. We have 144 tubes in a 12 by 12 square array, which have an inner diameter of one inch in an outer diameter of 1.2 inches. It is desired that the steam be condensed at a rate of ÂŁ6800 mass per hour and theâŠ
A body starts moving a velocity of 3m/s and moves in a straight-line motion with uniform acceleration. After 5 seconds of time, it gained the velocity of 5.5 m/s. fine uniform acceleration and the distanced travelled in 10 seconds.
You ran and made 2 laps around a 400m track. What were your average speed and average velocity if you ran for 200 seconds?
3. A man drops a ball off a cliff. If it is travelling 40m/s just before it hits the ground, how tall is the cliff? (a=9.81m/s^2).
the pressure of helium gas is initially 35 atmospheres after many balloons been blown up,the pressure has decreased to 5 atmospheres.what fraction of the original gas remains in the cylinder
determine the magnitude of the vector sum
Suppose you are sitting, naked, on a steel bench with a temperature of 10°C. The only thing insulating the core of your body (temperature 37°C) is a layer of skin (the epidermis and dermis together are about 4 mm thick) and fat (varies from individual to individual, but a typical thicknessâŠ
The temperature of the walls in a room is significant determinant of comfort; a quick calculation can show why. (The calculation is a bit artificial, but the point is clear.) A human has about 1.8 m2 of skin. If a person is unclothed in dry air of 24°C, the skin will be about 33°C. SupposeâŠ
If you get a cup of coffee in a paper cup, you may be given a corrugated paper sleeve to put around it to make it comfortable to hold. Explain the purpose of the paper sleeve, and how it accomplishes this. Why is the paper sleeve corrugated?
Jason, a 60 kg cyclist, is pedaling his bike at a good clip, using a total energy of 400 W. As he exercises, his body will start to warm up, and he will perspire to keep himself cool. A. Assuming Jasonâs pedaling has a typical 25% efficiency, by how much would his body temperature riseâŠ
On a hot summer day, a cup of flavored shaved ice can be a welcome treat. Suppose you ignore the obvious âbrain freezeâ danger and eat an 8 oz (0.22 kg) cup of ice rather quickly. When it melts in your stomach, how much will this reduce your body temperature? How much heat is needed to meltâŠ
In the United States, railroad cars ride on steel rails. Until the mid-1900s, most track consisted of 11.9 m lengths connected with expansion joints that allow for the rails to expand and contract with temperature. If a section of rail is exactly 11.900 m long on a hot, sunny day when it warmsâŠ
Your lungs have a volume of approximately 4.0 L. While visiting the seaside on a chilly 10ÂșC day, you quickly take a deep breath, all your lungs can hold. The air quickly heats up to your body temperature of 37ÂșC. Assume that you hold the volume of your lungs constant, and that the numberâŠ
A child attending a carnival in a quaint seaside town has been given a spherical helium balloon that is 30 cm in diameter. How many moles of helium does the balloon contain? She âwants to keep the balloon fresh,â so she puts in the freezer, cooling it down from the hot 28°C outside âŠ
A child has been given a helium balloon. Ignoring repeated parental suggestions of tying it to his wrist, he lets it go so that it rapidly rises into the sky. As the balloon rises, it expands, because the pressure of the atmosphere decreases. Ignoring heat exchanges with the atmosphere (aâŠ
What are the rms speeds of a nitrogen molecule (mass ? 10?26 kg) at the following temperatures? Room temperature of 68ÂșF (20ÂșC) The coldest temperature ever observed on earth, ?129ÂșF (?89ÂșC) Polar night on Mars, ?133ÂșC The coldest temperature achieved in the laboratory, 0.5 nK
If 50g of ice at -10 degrees Celsius is added to 300 cm ^ 3 of water at 25 degrees Celsius in a 100g Al calorimeter. What is the final temperature, in degrees Celsius?
A lamp consumes 1000 J of electrical energy in 10 s. Calculate its power.
Calculate the kinetic energy of a body of mass 2 kg moving with a velocity of 0.1 m/s.
How much work should be done on an object of mass 120 kg to increase its velocity from 25 m/s to 40 m/s?
Calculate the power of an electric motor that can lift 800 kg of water ti store in a tank at a height of 1500 cm in 20 s.(g=10 m/s^2)
Calculate the force of gravitation between two objects of masses 50 kg and 120 kg respectively, kept at a distance of 10 m from each other. (G=6.673 x 10^-11 kg m/s
A body of mass 500 g is at rest on a frictionless surface. Calculate the distance travelled by it in 10 s when acted upon by a force of 10^-2 N.
It is required to increase the velocity of a scooter of mass 80 kg from 5 m/s to 25 m/s in 2 seconds. Calculate the force required.
When a force of 40N is applied on a body, it moves with an acceleration of 5 m/s^2. Calculate the mass of the body.
When a missile is fired from a tank, it gets a momentum of 2000 Kg m/s. If the velocity of the missile is 50 m/s, calculate the mass of the missile.
A 2 kg metal block at 50 degrees Celsius is placed in contact with another 1 kg piece of the same metal at 20 degrees Celsius. What will be the final temperature of both?
How much heat of energy is needed to convert 10 kg of water at 50 degrees C into water vapor at 120 degrees C?
Silver's melting point is 960 degrees Celsius and its specific heat is 0.056 cal / g. Its heat of fusion is 21.1 cal / g.
A 50g piece of metal is heated to 200 degrees Celsius and dropped into a plastic cup containing 0.4 kg of 20 degrees Celsius water. If the thermal equilibrium is established at 22.4 degrees Celsius, find the specific heat of the metal in Kcal / kg degrees Celsius.
A 100g mass copper calorimeter contains 150g of water and 8g of ice in thermal equilibrium at atmospheric pressure. 100g of lead at 200 degrees Celsius are introduced into the calorimeter. Find the final temperature, in degrees Celsius, if there is no release of heat to the environment.
A 2.0 kg block of aluminum has an initial temperature of 10 degrees C. If 140 kJ of heat is added to the block, what is the final temperature, in degrees Celsius?
A student heats a 10 g iron nail (specific heat of 464 J/(kg C) ) with a flame. The nail is then put into 100 g of water at 10 C. The water temperature rose to 20 C, what was the initial temperature of the nail?(specific heat of water is 4186 J/(kg C) )
150 kcal of heat increases the temperature of 2 kg of material to 400 degrees F. What is the specific heat of the material in Kcal / kg x degrees C?
05. Pure tones of 2, 6, and 12 Hz are played near a taut string, and only the 12Hz tone causes the string to vibrate in one of its modes; from this information what are the possible LNRF of the string? a. 3Hz b. 4Hz c. 6Hz d. 12Hz e. more than one of the above
angular kinematics and torque
3. Hallar la ecuaciĂłn dimensional de "s" en la siguiente fĂłrmula fĂsica. \[ \frac{V^{2} A}{T}=-s a+Q \] \( V= \) Velocidad; \( A= \) ĂĄrea; \( T= \) tiempo; \( \mathrm{a}= \) aceleraciĂłn a) \( L^{2} T^{2} \) b) LT d) \( L^{3} T^{-1} \) e) \( L^{-3} T \) c) \( L^{3} T \)
The partial pressure of ether ????1 over a solution of acetone in ether at 30°C is 0.713 bar at a mole fraction of acetone, ????2 =0.200. The partial pressure of acetone ????2 at this same concentration is 0.120 bar. Given that the partial pressures for the pure components are ????2?âŠ