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. What is the actual weight of a body having mass 10 kg ?
A) 9.8N 8) -9.8N C) 98N 0) -98N

. What is the velocity of Radio waves in free space ?
A) 3x 108 17.571 8) 6x 108 11.51 0) 1x 108 11.51 0) 2 >‹ 108 71.51

. Ahalf wave rectifier produces 80 watts output power when an ೩.೦. power of 200 watts
is applied as input. What is the rectification efficiency ?

A) 80% B) 40% C) 2.5% D) 25%

. Which of the following electromagnetic radiation is used for producing crystal
diffraction patterns ?

A) Visible light B) X-rays
C) Radio waves D) Infrared radiations

. The self destruction of an unstabilised transistor by thermal run away is caused by
A) Emitter current B) Base current
C) Collector current D) All

. Oscillator in an electronic circuit is used for
A) Energy conversion B) Energy production
C) Energy destruction D) No effect

. Identify the reason for getting different colours in the case of oil spread over water.
A) Non-uniform thickness B) Non-uniform inclination

C) Non-uniform thickness and inclination D) None

. Where do we find maximum cosmic ray intensity ?
A) Between poles and equator B) Equator

C) Geomagnetic poles D) Below sea level

. Which is the main energy source of sun ?
A) Organic fuels B) Radiation from other galaxies

C) Fusion reaction D) Fission reaction