Question

Question No. 1
A body weighs 180N on the surface of the earth. How much will it weigh at depth R. /2 from surface of the earth.
(R = Radius of earth)
90 N
o 100 N
O 120 N
O 150 N​

Answer 1

Explanation:

Acceleration due to gravity at height h from the Earths surface is given by the relation:

g

′

=

(1+

R

e

h

)

2

g

Substituting h=R

e

/2,

g

′

=4g/9

Weight of body of mass m at height h is given as:

W

′

=mg

′

=4/9 mg

=4/9×63=28 N

Answer 2

Given - Body weight - 180 Newton

Depth - R/2 from surface of Earth.

Find - Weight at given depth.

Solution - To find body weigh at the surface of Earth, the formula used will be : W' = W (1-d/R). In the formula, W' is new weigh, W is original weigh, d is depth and R is radius of Earth.

Keeping the values in equation-

W' = 180 (1-R/2R)

W' = 180 (1-1/2)

W' = 180*1/2

W' = 90

Hence, the new body weigh will be 90 Newton.