Work and Energy Class 9th

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

Tags

NGSS.MS-PS3-2

NGSS.MS-PS3-5

A car is accelerated on a levelled road and attains a velocity 4 times of its initial velocity. In this process the potential energy of the car

• (a) does not change

• (b) becomes twice to that of initial

• (c) becomes 4 times that of initial

• (d) becomes 16 times that of initial

Tags

NGSS.MS-PS3-2

In case of negative work the angle between the force and displacement is

• (a) $0\degree$

• (b) $45\degree$

• (c) $90\degree$

• (d ) $180\degree$

A car is accelerated on a levelled road and attains a velocity 4 times of its initial velocity. In this process the potential energy of the car

• (a) does not change

• (b) becomes twice to that of initial

• (c) becomes 4 times that of initial

• (d) becomes 16 times that of initial

Tags

NGSS.MS-PS3-2

An iron sphere of mass 10 kg has the same diameter as an aluminium sphere of mass is 3.5 kg. Both spheres are dropped simultaneously from a tower. When they are 10 m above the ground, they have the same

• (a) acceleration

• (b) momenta

• (c) potential energy

• (d) kinetic energy

Tags

NGSS.MS-PS3-1

NGSS.MS-PS3-2

NGSS.MS-PS3-5

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)

• $6\times10^{3\ ^{ }}$ J

  
  

• $6$ J

• 0.6 J

• zero

Which one of the following is not the unit of energy?

• (a) joule

• (b) newton metre

• (c) kilowatt

• (d) kilowatt hour

The work done on an object does not depend upon the

• (a) displacement

• (b) force applied

• (c) angle between force and displacement

• (d) initial velocity of the object

Water stored in a dam possesses

• (a) no energy

• (b) electrical energy

• (c) kinetic energy

• (d) potential energy

Tags

NGSS.MS-PS3-2

If speed of a car becomes 2 times, its kinetic energy becomes

• 4 times

• 8 times

• 16 times

• 12 times

Tags

NGSS.MS-PS3-1