The power factor of the circuit shown in the figure is

1.  0.2

2.  0.4

3.  0.8

4.  0.6

A particle is executing linear simple harmonic motion of amplitude A. What fraction of the total energy is kinetic when the displacement is half the amplitude

1.  

Two simple harmonic motions are represented by y₁=4sin$\left(4\pi t-\frac{\pi }{2}\right)$ and y₂= 3cos(4πt). The resultant amplitude is

 

1.  7

Three plates of common surface area A are connected as shown in figure. The effective capacitance will be 

 

1.  3ε₀A/d

When 20 J of work was done on the gas, 40 J of heat energy was released. If the initial internal energy of the gas was 70 J, what is the final internal energy?

1.  50 J

2.  -150 J

3.  90 J

4.  110 J

The value of g at a particular point is 9.8 ms^-2. Suppose the earth suddenly shrinks uniformly to half its present size without losing any mass. The value of g at the same point (distance of the point from the centre of earth does not change) will now be

 

1.  9.8 ms^-2

A spherical ball is dropped in a long column of viscous liquid. Which of the following 
graphs represent the variation of 
(i) gravitational force with time 
(ii) viscous force with time 
(iii) net force acting on the ball with time? 

 

1.  Q, R, P

The young’s modulus of a wire of length L and radius r is y newton per square metre. If the length is reduced to  and radius . Its young’s modulus will be

 

1.  

A boy of mass m stands on one end of a wooden plank of length L and mas M. The plank is floating on water. If the boy walks from one end of the plank to the other end at a constant speed, the resulting displacement of the plank is given by

 

1.