Question Detail

The force which opposes the relative motion between different layers of liquid or gases is called

Critical Velocity
Streamline Flow
Terminal Velocity
Viscous Force

Answer: Option D

Explanation:

Critical Velocity - The maximum velocity upto which fluid motion is streamline is called Critical Velocity.

Streamline Flow - If velocity of all fluid particles is same all the time then it can be said in streamline flow.

Terminal Velocity - When a body falls in viscous medium, its velocity first increases and finally becomes constant. The constant velocity is called terminal velocity.

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. 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.

3. The angle of reflection is equal to the angle of incidence.

True
False

Answer: Option A

4. Alfred Nobel invented

X ray
Diesel Engine
Dynamite
Dynamo

Answer: Option C

Explanation:

Alfred Nobel if Sweden invented Dynamite in 1867,

X ray was invented by Wilhelm Roentgen of Germany in 1895,

Diesel Engine was invented by Rudolf Diesel of Germany 1892,

Dynamo was invented by Michael Faraday of England in 1831.