Question Detail

Which of the following is an electromagnetic wave ?

Cathode rays
Sound wave
Ultrasonic wave
Infra red rays

Answer: Option D

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

True
False

Answer: Option A

2. Force of attraction between the molecules of different substances is called

Surface tension
Cohensive force
Adhesive force
None of above

Answer: Option C

Explanation:

Cohensive force - Force of attraction between the molecules of same substance is called Cohensive force.

3. Which instrument is used to measure the scattering of light by particles suspended in a liquid ?

Nephetometer
Ohmmeter
Ondometer
Pyrometer

Answer: Option A

Explanation:

Ohmmeter - is used to measure electrical resistance in ohms,

Ondometer - is used to measure frequency of electromagnetic waves,

Pyrometer - is used to measure very high temperature.

4. All planets move around the sun in elliptical orbits, with the sun being at rest at one focus of the orbit.

True
False

Answer: Option A

5. Which instrument is used in submarine to see the objects above sea level ?

Pykometer
Polygraph
Photometer
Periscope

Answer: Option D

Explanation:

Pykometer - used to determine the density and coefficient of expansion of liquids,

Polygraph - used to record changes in heartbeat, blood-pressure and respiration,

Photometer - used to compare luminous intensity of the source of light.