Question

Masses of large objects like stars and planets can be determined by using
(1) Doppler’s effect
(2) Mass spectrograph
(3) Tunnelling microscopy
(4) Newton’s law of gravitation

Answer 1

Answer:

(1) Doppler’s effect

Explanation:

Masses of large objects like stars and planets can be determined by using Doppler’s effect

Answer 2

Masses of large objects like stars and planets can be determined by using (4) Newton’s law of gravitation.

• Newton's law of gravitation states that there is a force of attraction between two objects placed at some distance r.
• The formula for finding gravitational force = Gm1m2\r².
• Here, G is the gravitational constant and m1 and m2 are the masses of two objects.
• Doppler effect is used to calculate the relative frequency or velocity of the observer when moving towards or away from the source.
• The mass spectrograph is used to find charge by mass ratio to know the differences in sizes of atoms and ions.
• Tunnelling microscopy is used in industries to grab atomic images of substances.