Question

A large ball 2 m in radius is made up of a
rope of square cross section with edge
length 4 mm. Neglecting the air gaps in
the ball, what is the total length of the
rope to the nearest order of magnitude?​

Answer 1

Dear Student,

◆ Answer -

l = 2.094×10^6 m

◆ Explanation -

# Given -

r = 2 m

s = 4 mm = 4×10^-3 m

# Solution -

Volume of ball is given by -

Vb = 4/3 πr^3

Vb = 4/3 × 3.142 × 2^3

Vb = 33.51 m^3

As ball is made from the rope, volume of rope must have been same.

Vr = Vb

l × s^2 = Vb

l × (4×10^-3)^2 = 33.51

l = 33.51 / 16×10^-6

l = 2.094×10^6 m

Therefore, total length of wire must have been 2.094×10^6 m.

Thanks dear...