Question Detail

David Hughes invented

Machine Gun
Microphone
Microscope
Motorcycle

Answer: Option B

Explanation:

David Hughes of USA invented Microphone in 1878,

Machine Gun was invented by Richard Gatling of USA in 1861,

Microscope was invented by Z. Jansen of Netherlands in 1590,

Motorcycle was invented by Edward Butler of England in 1884.

1. 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.

2. Which instrument is used to determine the intensity of colours ?

Cathetometer
Chronometer
Colorimeter
Commutator

Answer: Option C

Explanation:

Cathetometer - is used to determine heights,

Chronometer - is used to longitude of a vessel at sea,

Commutator - is used to convert AC to DC.

3. Which instrument is used to measure pressure of gases ?

Manometer
Machmeter
Magnetometer
Micrometer

Answer: Option A

Explanation:

Machmeter - is used to determine the speed of an aircraft in terms of speed of sound,

Magnetometer - is used to compare magnetic movements and fields,

Micrometer - is used to convert sound waves into electrical vibrations.

4. Which instrument is used to measure the power of electric circuit ?

Voltmeter
Wattmeter
Wavemeter
Viscometer

Answer: Option B

Explanation:

Voltmeter - is used to measure electric potential difference between two points,
Wavemeter - is used to measure the wavelength of a radiowave,
Viscometer - is used measure viscosity of liquid.

5. Radiocarbon is produced in the atmosphere as a result of

collision between fast neutrons and nitrogen nuclei present in the atmosphere
action of ultraviolet light from the sun on atmospheric oxygen
action of solar radiations particularly cosmic rays on carbon dioxide present in the atmosphere
lightning discharge in atmosphere

Answer: Option A