Physics Past Questions and Answers

The function of a 5-A fuse included in a circuit supplying a household refrigerator with power is to keep the

A Temperature of the refrigerator low and constant
B Keep current supplied to the refrigerator below 5A
C Voltage supply constant
D Current supplies to the refrigeration

Question 37:

The fig above shows a uniform circular object, center R and diameter PS. A circular section 6 and Diameter PR is cut from it. if PQRS is a straight line, where is center of gravity of the figure

A Q
B R
C A point between P and R
D A point between R and S

Question 38:

A simple pendulum of mass m moves along an arc pf a circle radius R in a vertical plane as shown above. What is the work done by gravity in a downward swing through the angle q to 0 degree

A MgR sinÎ¸
B MgR (1- cos θ)
C MgR
D MgR (1 - sinÎ¸)

Question 39:

A block of mass m is held in equilibrium against a vertical wall by a horizontal force. If the coefficient of friction between the wall and the block is µ, the minimum value of the horizontal force is

A Âµmg
B (1-µ)mg
C (1+Âµ)mg
D Mg/Âµ

Question 40:

In the fig above W1 = 200g, and W2 =450g . Calculate the extension of the spring per unit load?
[g = 10ms^-2]

A 6.0 x 10^-5mN^-1
B 2.5 x 10^-4mN^-1
C 6.0 x 10 ^-3mN^-1
D 2.5 x 10 ^-2mN^-1