41) If no external force acts on a system of bodies, the total linear momentum of the system of bodies remains constant. Which law states that ?
a) Newton’s first law
b) Newton’s Second Law
c) Newton’s Third Law
d) Principle of conservation of linear momentum
42) Bolometer is used to measure
a) Frequency
b) Temperature
c) Velocity
d) Wavelength
43) The nuclear reaction in which a heavy nucleus splits into two nuclei of nearly equal mass is called
a) Nuclear fusion
b) Nuclear fission
c) Nuclear reaction
d)Fast breeding
44) Which instrument is used to measure depth of ocean ?
a)Galvanometer
b)Fluxmeter
c)Endoscope
d)Fathometer
45) Light year is a unit of
a) time
b) distance
c) light
d) intensity of light
46) Intensity of sound at a point is ____ its distance from the source.
a) directly proportional to
b) inversely proportional to
c) directly proportional to square of
d) inversely proportional to square of
47) A man presses more weight on earth at :
a) Sitting position
b) Standing Position
c) Lying Position
d) None of these
48) Energy possessed by a body in motion is called
a) Kinetic Energy
b) Potential Energy
c) Both A and B
d) None of these
49) A piece of ice is dropped in a vesel containing kerosene. When ice melts, the level of kerosene will
a) Rise
b) Fall
c) Remain Same
d) None of these
50) Stars appears to move from east to west because
a) all stars move from east to west
b) the earth rotates from west to east
c) the earth rotates from east to west
d) the background of the stars moves from west to east