Question Detail

What is refractive index ?

it is defined as the ratio of speed of light in the medium to the speed of light in vacuum.
it is defined as the ratio of speed of light in vacuum to the speed of light in the medium .
it is defined as the product of speed of light in medium and in vacuum.
None of above

Answer: Option B

1. What is Hooke's Law ?

Stress is inversely proportional to strain.
Stress is directly proportional to strain.
Stress and strain are dependent on each other.
Stress and strain are independent of each other.

Answer: Option B

2. Who discovered Atom ?

Madam Curie
James Chadwick
Rutherford
John Dalton

Answer: Option D

Explanation:

John Dalton discovered Atom in 1808,

Madam Curie discovered Radium in 1898,

James Chadwick discovered Neutron in 1932,

Rutherford discovered Proton in 1919.

3. What is escape velocity ?

Escape velocity is the maximum velocity with which a body should be projected from the surface of earth so it do not go beyond gravitational field of earth.
Escape velocity is the minimum velocity with which a body should be projected from the surface of earth so it do not go beyond gravitational field of earth.
Escape velocity is the minimum velocity with which a body should be projected from the surface of earth so as it goes out of gravitational field of earth and never return to earth.
Escape velocity is the maximum velocity with which a body should be projected from the surface of earth so as it goes out of gravitational field of earth and never return to earth.

Answer: Option C

4. Force of attraction between the molecules of different substances is called

Surface tension
Cohensive force
Adhesive force
None of above

Answer: Option C

Explanation:

Cohensive force - Force of attraction between the molecules of same substance is called Cohensive force.

5. Which instrument is used to measure altitudes in aircraft's ?

Audiometer
Ammeter
Altimeter
Anemometer

Answer: Option C

Explanation:

Ammeter - Measures strength of electric current.

Audiometer - Measures intensity of sound.

Anemometer - Measures force and velocity of wind and directions.