Question

A Ping-Pong ball has a diameter of 2.55 cm and average density of 0.116 g/cm3 . What force would be required to hold it completely submerged under water?

Answer 1

Answer:

F = 0.075 N

Explanation:

given,

diameter of ping pong ball = 2.55 cm

average density of the ball = 0.116 g/cm³

Force require to hold the ball completely submerged= ?

Volume of the ball

$V = \dfrac{4}{3} \pi r^3$

$V = \dfrac{4}{3} \pi (\dfrac{2.55}{2})^3$

    V = 8.63 cm³

density of water = 1 g/cm³

force required to keep the ball submerged is equal to

$F = \rho_w V_w g - \rho_b V g$

$F = 1\times 8.63\times g - 0.116 \times 8.63 \times g$

F = 7.63 x 9.8 x 10⁻³

F = 0.075 N

Force required to keep the ball inside the water is equal to 0.075 N