RRB NTPC 2020 General Science Physics Important Questions

1. Which of the following is false?

Sound waves are ____________ waves.

1. Pressure
2. Longitudinal
3. Electromagnetic
4. Mechanical

Explanation: Electromagnetic waves are not like sound waves because they do not need molecules to travel. This means that electromagnetic waves can travel through air, solid objects and even space.

2. Which of the following coloured light has the lowest frequency?

1. Green
2. Blue
3. Red
4. Violet

Explanation: Red has the longest wavelength among the given options.

From VIBGYOR - R (red) has the longest and V(violet) has the shortest

It is reverse for frequency.

3. An electric motor converts

1. Mechanical energy into electrical energy.
2. Thermal energy into electrical energy.
3. Electrical energy into mechanical energy.
4. Radiant energy into electrical energy.

Explanation: An electric motor converts electrical energy to mechanical energy.

4. Which one is not a good conductor of electricity?

1. Porcelain
2. Aluminum
3. Tungsten
4. Nickel

Explanation: Porcelain is an excellent insulator for use at high voltage.

5. The technology developed to track enemy submarines in World War II was

2. SONAR
3. Echolocation
4. LIDAR

Explanation: Two similar but different technological advances that figured prominently in the Allied victory in World War II were radar and sonar, both techniques for detecting the location and speed of enemy aircraft or submarines.

6. The first large scale electrical air conditioning was invented and used in 1902 by:

1. Willis Carrier
2. John Gorrie
3. Stuart Cramer
4. H. H. Schultz

Explanation: Modern air conditioning emerged from advances in chemistry during the 19th century, and the first large-scale electrical air conditioning was invented and used in 1902 by Willis Haviland Carrier.

7. Zero degree centigrade is equal to what degree Fahrenheit?

1. 100°F
2. 30°F
3. 34°F
4. 32°F

Explanation: 0°C is equal to 32°F.

8. What is the gravitational force exerted on a mass called?

1. Stress
2. Inertia
3. Weight
4. Work

Explanation: The gravitational force exerted on an object near the earth's surface is called the object's weight.

9. The earth conductor provides a path to ground for:

1. Circuit Current
2. Leakage Current
3. Over Current
4. High Voltage

Explanation: To pass the leakage current to the earth.

10. A galvanometer is converted to a voltmeter by:

1. adding a high resistance in series with the galvanometer
2. adding a low resistance in parallel with the galvanometer
3. increasing the number of windings of galvanometer coil
4. decreasing the number of windings of the galvanometer coil