1.
A body of mass 4 kg is moving with a speed of 5 m/s. Its kinetic energy is
2.
A force of 40 N acts on a body through a displacement of 5 m making an angle of 60⁰ with displacement. The work done is
3.
A body falls freely from a height. Ignoring air resistance, during the fall
4.
Which one is not a conservative force?
5.
The work done by centripetal force in uniform circular motion is
6.
Power developed by an engine moving with constant velocity is
7.
A body has kinetic energy K. If its momentum is doubled, its kinetic energy becomes
8.
A spring is stretched by 20 cm. If the extension is doubled, the elastic potential energy becomes
9.
The dimensional formula of power is
10.
A machine does 6000 J of work in 30 s. Its power is
11.
Q51. Assertion (A): The work done by gravity depends only on the initial and final positions. Reason (R): Gravity is a conservative force.
12.
Assertion (A): A body moving with constant speed may require power. Reason (R): Power is needed to overcome resistive forces like friction.
13.
A force-displacement graph is a straight line passing through the origin. The work done equals
14.
The efficiency of an ideal machine is
15.
Match the Columns: Column–I P. Kinetic Energy Q. Potential Energy R. Power S. Work Column–II 1. Joule 2. Watt 3. (1/2)mv² 4. mgh
16.
If the speed of a particle becomes three times, its kinetic energy becomes
17.
A man climbs a staircase carrying a load. The work done against gravity depends on
18.
Which graph is most suitable for calculating work done by a variable force?
19.
The commercial unit of electrical energy is
20.
A body is projected vertically upward. At the highest point its
Leave a Reply