The bricks, each 6.0 cm thick and mass 1.5 kg, lie flat on a table. How much work is required to stack them one on the top of another?
Correct answer: C. 40 J
- A. 10 J
- B. 15 J
- C. 40 J
- D. 150 J
Explanation
W = n (n - 1) / 2 * mgh = 10 (10 - 1) / 2 * mgh = 45 mghW = 40 J
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Work and Energy
Work transfers energy when a force causes displacement, while kinetic energy, gravitational potential energy and power describe motion, position and the rate of energy transfer. The work-energy theorem links net work with change in kinetic energy, and efficiency accounts for energy losses rather than treating them as energy destruction.
Practise Work and Energy
748 free Work and Energy MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Physics questions like this
Physics is on 16 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Work and Energy questions
A bomb of mass 30 kg at rest explodes into two pieces of masses 18 kg and 12 kg. The velocity of 18 kg mass is 6 m s-1. The K.E of other mass is
Kinetic energy of a body moving with speed of 10 m s-1 is 30 J. If its speed becomes 30 m/s its K.E will be:
The velocity and momentum of a moving body are 10,000 cm s-1 and 10,000 g cm s-1 respectively. The K.E will be:
A ball is thrown vertically upwards. Neglecting air resistance, which statement is correct?
A 500N force is applied on an object and it moves with velocity 10 ms-1. If value of power is 2500 watt. Then what will be the angle between force and displacement
The time taken by an engine of power 10 kW to lift a mass of 200 kg to the height 440 m is