Question Detail

K. Macmillan invented

Bicycle
Barometer
Calculating Machine
Centigrade Scale

Answer: Option A

Explanation:

K. Macmillan of Scotland invented Bicycle in 1839.

Barometer was invented by E. Torricelli of Italy in 1644.

Calculating Machine was invented by Pascal of France in 1642.

Centigrade Scale was invented by A. Celsius of France in 1742.

1. Marie and Pierre Curie invented

Radio
Radium
Radar
Refrigerator

Answer: Option B

Explanation:

Marie and Pierre Curie of France invented Radium in 1898,

Radio was invented by G. Marconi of England in 1901,

Radar was invented by Dr. A.H. Taylor and L.C. Young of USA in 1922,

Refrigerator was invented by J. Harrison and A. Catlin of Britain in 1834.

2. Which of the following is an electromagnetic wave ?

Cathode rays
Sound wave
Ultrasonic wave
Infra red rays

Answer: Option D

3. The rotational effect of a force on a body about an axis of rotation is described in terms of

Centre of gravity
Centripetal force
Centrifugal force
Moment of force

Answer: Option D

4. Orbital speed of a satellite is dependent of its mass.

True
False

Answer: Option B

Explanation:

Orbital speed of a satellite is independent of its mass.

5. 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.