Rabin Kalikote

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Show that 'g' produced by a freely falling body is independent of its mass.

Let us consider a body of mass 'm' falling towards the center of any heavenly body of mass 'M' and radius 'R' with the acceleration due to gravity 'g'.

So, force of attraction = (G.M.m)/R²

or, mg =(G.M.m)/R²
or, g = (G.M)/R²

Hence, g produced in any body falling freely has no effects by its mass.

What is gravity? Write down its SI unit. Write down any three effects of gravity.

The force of attraction of any heavenly bodies by which any bodies on its surface is attracted towards its center is called gravity.Its SI unit is Newton (N).

Any three effects of gravity are:

Falling of objects towards the center of the earth.
Flowing of rivers.
Stability of large buildings and bridges.
Existence of atmosphere on the surface of the earth.

Write the difference between:a. Gravitational constant (G) and acceleration due to gravity (g).b. Gravity and Gravitation force.c. Gravity and acceleration due to gravity.d. Mass and weight.e. Free...

a. Gravitational constant (G) and acceleration due to gravity (g)

G	g
It is the force of attraction between 2 bodies of mass 1 kg each kept at the distance of 1m between their centers.	It is the acceleration produced on freely falling bodies due to the influence of gravity.
It is a constant value.	It is a variable value.
Its unit is Nm²/kg².	Its unit is m/s².

b. Gravity and gravitational force.

Gravity	Gravitational force
It is the force of attraction by which any body is attracted...

Define the following terms:a. Universal gravitational constant.b. Gravitation field.c. Acceleration due to gravity.d. Freefall.e. Weightlessness.

a. Universal gravitational constant:
G is defined as the force of attraction between two bodies of mass 1 kg each kept at a distance of 1 m apart from their centers.

b. Gravitational field:
The gravitational field is the field around any body or heavenly body where the force of attraction by that body is experienced.

c. Acceleration due to gravity:
Acceleration produced on a freely falling body due to the influence of gravity is called acceleration due to gravity.

d. Freefall:
When a body is falling...

State Newton's law of gravitation and prove that F = (G m1m1) / d2

Newton's law of gravitation states that "Everybody in the universe attracts every other body with the force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers".

So,F m₁m₂.......... relation 1
F 1/d².......... relation 2

From relation 1 and 2:
F (m₁m₂)/d²F = G .(m₁m₂)/d²

Where G is gravitational constant as a proportional constant.

What is gravitational force? Write its SI unit.

Gravitational force is the force of attraction by which a body is attracted towards the center of the earth or any other havenly bodies if the body is on or near the surface.

Its SI unit is Newton (N).

What is the minimum distance between a source of the sound and a reflector to hear an echo?

Let S be the distance between the source of sound and reflector.
V be the velocityof sound in air.
t be the total time taken by the sound to travel from source to reflectorand back to the source.

2S = Vt
or,S = (Vt)/2

We can hear distinct sounds if they reach our ear after an interval of 0.1s or more
That is, t = 0.1s and V = 340 ms^-1

Therefore, S = (340 x 0.1)/2 = 17 m.
This is required minimum distance to hear an echo.