Suppose you slowly and at constant speed lift a 4N book from the floor to a shelf 2m above the floor.
1a) While you're lifting it the net force on the book is zero (T, F)
1b) While you're lifting it the force by your hand against the book is 4N(T,F)
1c) The net work done on the book is zero (T, F)
1d) The work done by your hand on the book is 8 Joules (T, F)
1e) The net work done by the gravitational force is minus 8 Joules (T, F)
A car is traveling on a highway at a constant speed of 20m(i)/(h)r.
2a) The net work done on the car is zerd ( T,F
2b) The work done by the ground on the drive wheels is positive while the work done by the air drag and deformation within the tires and the wheels has the same magnitude but negative ( T,F )
2c) The car later speeds up to a speed of 40m(i)/(h)r. The kinetic energy of the car is now 4 times greater (T, F)
2d) Since the speed of the car in part (2c) is 2 times greater than the original speed the stopping distance should approximately increase to 2 times the original stopping distance ( T,F ).
If the potential energy of a book relative to ground is 2 Joules when the book is 1 meter above the ground, neglecting air resistance the kinetic energy of the book right before hitting the floor is
3a) 2J if released from rest (T, F)
3b) more than 2 joules if thrown downward from the same height (T, F)
3c) more than 2 joules if thrown upward from the same height (T, F)
3d) If air resistance is present less than 2J if released from rest (T, F)
You do 200J of work in 61 seconds, and your friend does the same work in 1 minute. It follows that your friend is more powerful than you are (T,F)
A weightlifter slowly lifts a mass of 50kg barbell from the floor to a height of 0.5 meter. (a) The work done by the weightlifter on the barbell is 245J (T, F) (b) The work done by the gravitational force is -245J (T, F)
If the net work done on a truck is 15000J and the truck's final kinetic energy is 45000J then truck's initial kinetic energy is 30000J(T,F)
MacBook Pro
kinetic energy is 30000J T,F) friend is more powerful than you are (T, F) 3d) If air resistance is present less than 2 J if released from rest (T, F) 3c) more than 2 joules if thrown upward from the same height (T, F) 3b) more than 2 joules if thrown downward from the same height (T, F) 3a2 J if released from rest T, F approximately increase to 2 times the original stopping distance (T, F). deformation within the tires and the wheels has the same magnitude but negative (T, F) 2aThe net work done on the car is zerT,F 2b) The work done by the ground on the drive wheels is positive while the work done by the air drag and 2 A car is traveling on a highway at a constant speed of 20 mi/hr. 1e) The net work done by the gravitational force is minus 8 Joules (T, F) 1d) The work done by your hand on the book is 8 Joules (T,F) 1e) The net work done on the book is zero (T, F) MacBook Pro 6 If the net work done on a truck is 15000 J and the trucks final kinetic energy is 45000 J then truck's initial by the weightlifter on the barbell is 245J T,F)b) The work done by the gravitational force is -245J T,F) 5 A weightlifter slowly lifts a mass of 50 kg barbell from the floor to a height of 0.5 meter. (a The work done 4 You do 200 J of work in 61 seconds, and your friend does the same work in l minute. It follows that your 3If the potential cnergy ofa book relative to ground is 2 Joules when the book is I meter above the ground Ia) While youre lifting it the net force on the book is zero (T, F) 1 Suppose you slowly and at constant speed lift a 4 N book from the floor to a shelf 2 m above the floor. Page<2 Z0OM of2
