CBSE
The work done in carrying a charge Q once around a circle of radius r about a charge q at the centre is
Zero
In elastic collision
both momentum and kinetic energies are conserved
both momentum and kinetic energies are not conserved
only energy is conserved
only mechanical energy is conserved
The displacement x of a particle at time t moving under a constant force is t = + 3, x in metre, t in second. Find the work done by the interval from t = 0 to t= 6 s.
A body rolls down an inclined plane. If its kinetic energy of rotation is 40% of its kinetic energy of translation, then the body is
solid cylinder
solid sphere
disc
ring
The force F acting on a particle moving in a straight line is shown below. What is the work done by the force on the particle in the 1st metre of the trajectory ?
5 J
10 J
15 J
2.5 J
Force required to move a mass of 1 kg at rest on a horizontal rough plane (µ = 0.1 and g =9.8 ms-2) is
0.98 N
0.49 N
9.8 N
4.9 N
If the kinetic energy of a body changes by 20 %, then its momentum would change by
20 %
24 %
9.5 %
44 %
Two particles have masses m and 4m and their kinetic energies are in the ratio 2 : 1. What is the ratio of their linear momenta ?
Two blocks of 2 kg and 1 kg are in contact on a frictionless table. If a force of 3 N is applied on 2 kg block, then the force of contact between the two blocks will be
zero
1 N
2 N
3 N
A body of mass 3 kg acted upon by a constant force is displaced by S' metre, given by relation , where t is in second. Work done by the force in 2 is