CBSE
Multiple Choice QuestionsThe height of a water fall is 84 m. Assuming that the entire kinetic energy of falling water is converted into heat, the rise in temperature of the water will be
0.196°C
1.960°C
0.96°C
0.0196°C
Momentum of a body of mass 1 kg is 10 kg-m/s, then its kinetic energy will be
100 J
50 J
1000 J
200 J
A particle is acted upon by a conservative force F = N (no other force is acting on the particle). Under the influence of this force, particle moves from (0,0) to (-3m, 4m), then
work done by the force is 3 J
work done by the force is − 45 J
at (0, 0) speed of the particle must be zero
at (0, 0) speed of the particle must not be zero
The average kinetic energy of a hydrogen gas molecule at NTP will be (Boltzmann's constant k = 138 x 10-23 J/K)
0.186 × 10-20 J
0.372 × 10-20 J
0.56 × 10-20 J
5.6 × 10-20 J
A bomb of mass 16 kg at rest explodes into two pieces of masses 4 kg and 12 kg. The velocity of the 12 kg mass is 4 ms-1 . The kinetic energy of the other mass is
192 J
96 J
144 J
288 J
If the heat of 110 J is added to a gaseous system, whose internal energy is 40 J. Then the amount of external work done is
140 J
70 J
110 J
150 J
The driver of a truck travelling with a velocity v suddenly notice a brick wall infront of him at a distance r. How the driver avoid himself by crashing into the wall ?
By speeding up the truck
By applying a brake
By slowing down the truck
By taking a circular turn
If W1 , W2 and W3 represent the work done in moving a particle from A to B along three different paths 1, 2 and 3 respectively in the gravitational field of a point mass m shown in the figure, find the correct relation between W1 , W2 and W3 .
W1 > W2 > W3
W1 = W2 = W3
W1 < W2 < W3
W2 > W1 > W3
The potential energy of a certain spring when stretched through a distance x is 20 J. The amoµnt of work that must be done on this spring to stretch it through an additional distance will be
20 J
25 J
5 J
15 J
A steel ball is dropped from a height h and it makes a perfectly elastic collision with a horizontal plane. Following its initial release, it will make periodic motion with frequency
