Work and Energy Class 9 Quiz

What is the formula for kinetic energy?

• mass * velocity^2

• 1/2 * mass * velocity

• mass + velocity^2

• 1/2 * mass * velocity^2

Define potential energy.

• Energy due to temperature

• Energy due to color

• Energy due to position or state

• Energy due to motion

What is the unit of power?

• A

• kg

• W

• V

A force of 20 N is applied to move an object 5 meters. Calculate the work done.

• 100 J

• 50 J

• 200 J

• 10 J

What is the kinetic energy of an object with a mass of 8 kg and a velocity of 6 m/s?

• 72 J

• 100 J

• 144 J

• 48 J

Calculate the potential energy of an object with a mass of 3 kg and a height of 8 meters.

• 123.8 joules

• 235.2 joules

• 17.2 joules

• 56.4 joules

1KW = ?

• 1000w

• 100w

• 10000w

• none

Si unit of power

• Watt

• ma

• pa

• 1J/s

When a body falls freely towards the earth, then its total energy

• (a) increases

• (b) decreases

• (c) remains constant

• (d) first increases and then decreases

A girl is carrying a school bag of 3 kg mass on her back and moves 200 m on a levelled road. The work done against the gravitational force will be (g =10 m s–2)

• 0.6 J

• zero