Work ,energy and power

If displacement is in the direction of force,then work is ------

• Negative

• Positive

• Zeor

When body moves in a circular path and covers quarter part distance 10 m with speed 5 m/s ,how much is the work done by an object.

• 2J

• No work

State whether work is a scalar or vector quantity

• Vector

• Scalar

Calculate the change in KE of a moving body if its velocity is reduced to 1/3 rd of its initial velocity.

• 1:9

• 3:27

• 9:1

What should be the angle between the forces and displacement to get maximum and minimum work

• 90, 0 degree

• 0,90 degree

• 90,180 degree

When is the potential energy of an oscillating simple pendulum i) Maximum II ) Minimum

• Mean and Extreme position

• Extreme and mean position

Name the physical quantity in which is measured in Calorie? How it is related to SI unit.

• Work , 1 J = 1.6 x $10^{-19}$

• Work , 1 C= 4.18.J

• Energy , 1 C= 4.18.J

Name the quantity which is measured in kW

• Energy

• Power

• Work

Calculate the KE of a body of mass 0.11 kgand momentum 20 kgm/s

• 200 J

• 2000 W

• 2000 J

State the energy conversion takes place in Solar cell