### JEE Mains Previous Years Questions with Solutions

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1

### AIEEE 2002

If mass-energy equivalence is taken into account, when water is cooled to form ice, the mass of water should
A
increase
B
remain unchanged
C
decrease
D
first increase then decrease

## Explanation

When water is cooled to form ice, energy is released from water in the form of heat. As energy is equivalent to mass therefore when water is cooled to ice, its mass decreases.
2

### AIEEE 2002

Which of the following is more close to a black body?
A
black board paint
B
green leaves
C
black holes
D
red roses

## Explanation

Black board paint is quite approximately equal to black bodies.
3

### AIEEE 2002

Heat given to a body which raises its temperature by ${1^ \circ }C$ is
A
water equivalent
B
thermal capacity
C
specific heat
D

## Explanation

Heat required for raising the temperature of the whole body by ${1^ \circ }C$ is called the thermal capacity of the body.
4

A
spectrometer
B
pyrometer
C
nanometer
D
photometer

## Explanation

Pyrometer is used to detect infra-red radiation.