Lakhmir Singh and Manjit Kaur Solutions for Chapter: Work and Energy, Exercise 15: Questions Based on High Order Thinking Skills (HOTS)

In which of the following case the work done by a force will be maximum?

When the angle between the direction of force and direction of motion is $0^{\mathrm{o}}$ or ${90}^{\mathrm{o}}$.

How much work is done by the gravitational force of earth acting on a satellite moving around it in a circular path? Give reason for your answer.

A man is instructed to carry a package from the base camp at B to summit A of a hill at a height of $1200 \mathrm{metres}$. The man weighs $800 \mathrm{N}$ and the package weighs $200 \mathrm{N}$. If $g=10 \raisebox{1ex}{$\mathrm{m}$}\!\left/ \!\raisebox{-1ex}{${\mathrm{s}}^2$}\right.$, how much work does a man do against gravity?

A man is instructed to carry a package from the base camp at B to summit A of a hill at a height of $1200 \mathrm{metres}$. The man weighs $800 \mathrm{N}$ and the package weighs $200 \mathrm{N}$. If $g=10 \raisebox{1ex}{$\mathrm{m}$}\!\left/ \!\raisebox{-1ex}{${\mathrm{s}}^2$}\right.$. What is the potential energy of the package at A if it is assumed to be zero at B?

When a ball is thrown vertically upwards, its velocity goes on decreasing. What happens to its potential energy as its velocity becomes zero?

A man X goes to the top of a building by a vertical spiral staircase. Another man Y of the same mass goes to the top of the same building by a slanting ladder. Which of the two does more work against gravity and why?

When a ball is thrown inside a moving bus, does its kinetic energy depend on the speed of the bus? Explain.

A bullet of mass $15 \mathrm{g}$ has a speed of $400 \mathrm{m}/\mathrm{s}$. What is its kinetic energy? If the bullet strikes a thick target and is brought to rest in $2 \mathrm{c}\mathrm{m}$, calculate the average net force acting on the bullet. What happens to the kinetic energy originally in the bullet?