Work Done

Q.

A load of 100 kg is pulled up by 5 m. Calculate the work done. Take $g=9.8m{s}^{-2}$

1. 5000 J

2. 4900 J

3. 4800 J

4. 4700 J

Q. Consider the following statements:

A. Work done in the motion of a body over a closed loop is zero for every force in nature.

B. No work is done on a particle which remains at rest.

Which of these statement(s) is/are correct?

1. A only

2. B only

3. Both A and B
4. Neither A nor B

Q. You are climbing up the hill. Your muscular energy is transformed into kinetic and potential energy.

1. False
2. True

Q.

Explain four stored energies.

Q. Machines reduce the amount of work needed to do a job.

1. True
2. False

Q. Ram and Hari lifted a $20kg$ bag to a height of $20m.$ Ram took 5 minutes to complete the task while hari took 7 minutes to complete it. Which of the following statement(s) is/are correct about the given situation.

1. Work done by Ram and Hari is equal.
2. Work done by Ram and Hari is unequal.
3. Energy spent by Ram and Hari is equal.
4. Energy spent by Ram and Hari is unequal.

Q. What are the factors on which work depends?

Q. Work is said to be done when you are swimming forward in a pool.

1. True
2. False

Q. The work done can be more for the same displacement when ___.

1. force applied is more
2. force applied is less
3. no force is applied
4. same force is applied

Q.

Two children say A and B each weighing 20 kg climb a rope up to the height of 10 m. Child A takes 10 s and child B takes 20 s to climb.

State whether work performed by both the children is equal or different.

Q. Hulk tried to move the wall of a fortress, but unfortunately he was unable to do it. He applied a very large amount of force to do so. But still the wall did not move. Work done by hulk is zero.

1. True
2. False

Q. Manu lifted a bag for a height of 20 m and Harry lifted the same for a height of 40 m. Which of the following statement is true for the work done by Manu and Harry?

1. Manu did twice the amount of work than Harry.
2. Both did the same amount of work.
3. Harry did twice the amount of work than Manu.
4. Manu did thrice the amount of work than Harry.

Q.

Which of the following statements are correct when you are riding a bicycle?

1. The energy provided from the digestion of food is used to move the bicycle

2. The bicycle moves without spending your energy

3. The bicycle converts your energy into its motion

4. Kinetic energy is involved in this process

Q. Which of the following statement(s) is/are correct?

1. For same displacement, work done increases with increase in the applied force.
2. For same applied force, work done increases with decrease in displacement.
3. For same applied force, work done increases with increase in displacement.
4. For same displacement, work done increases with decrease in the applied force.

Q.

what is the significance of work energy theorem?

Q. Question 18
In each of the following a force, F is acting on an object of mass, m. The direction of displacement is from west to east shown by the longer arrow. Observe the diagrams carefully and state whether the work done by the force is negative, positive or zero.

Q. Match the types of work done with the corresponding direction of displacement with respect to force applied.

1. Same direction
2. No displacement
3. Oppposite direction

Q. A Person is holding a bucket of water by applying a vertical force of 100N. He first moves a horizontal distance of 5 m and then climbs up through stairs a vertical distance of 10 m. calculate the total work done by the person on the bucket.

Q. A block of weight 100 N is slowly moved up a smooth incline of inclination 37° by a person. Calculate the work done by the person in moving the block through a distance of 2 m, if the driving force is (a) parallel to the incline and (b) in the horizontal direction.