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. Who discovered Diode Bulb ?

Henry Becquerel
Sir J.S. Fleming
Lee De Forest
Archemedes

Answer: Option B

Explanation:

Sir J.S. Fleming discovered Diode Bulb in 1904,

Lee De Forest discovered Triode Bulb in 1906,

Archemedes discovered laws of floatation in 1827,

Henry Becquerel discovered Radioactivity in 1896.

2. Atom is the smallest part of matter which takes part in chemical reactions.

True
False

Answer: Option A

3. Light year is a unit of

Time
Light
Distance
Intensity of light

Answer: Option C

4. Radian is used to measure

Temperature
Intensity of Flame
Angle
Solid Angle

Answer: Option C

Explanation:

Kelvin is used to measure Temperature,

Candela is used to measure Intensity of flame,

Steredian is used to measure Solid Angle.

5. newton is used to measure

Speed
Volume
Force
Area

Answer: Option C