Question Detail

Which of following in not a property of cathode ray.

Cathode rays are invisible and travel in a straight line.
These rays can ionise gases.
These rays can penetrate through thin metal foils.
These rays make materials cool on which they fall.

Answer: Option D

Explanation:

These rays heat the materials on which they fall.

1. Which instrument is used to measure strength of direct current ?

Stroboscope
Streoscope
Tangent Galvanometer
Tachometer

Answer: Option C

Explanation:

Stroboscope - is used to view rapidly moving objects,

Streoscope - is used to view two dimensional pictures,

Tachometer - is used to determine rotational speed of a shaft (used in aeroplanes and motor boats).

2. Which instrument is used to record physical happenings at a distant place ?

Thermostat
Tonometer
Telemeter
Transponder

Answer: Option C

Explanation:

Thermostat - is used to regulate the temperature at a particular point.

Tonometer - is used to measure the pitch of a sound,

Transponder - is used to receive a signal and transmit a reply immediately.

3. What is the maximum value of deforming force upto which a material shows elastic property and above which the material loses it ?

Elasticity
Strain
Elastic Limit
Stress

Answer: Option C

4. 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.