Question

Tom has a mass of 75.0 kg and Sally has a mass of 47.0 kg. Tom and Sally are standing 20.0 m apart on the dance floor. Sally looks up and sees Tom. She feels an attraction. If the attraction is gravitational, find its size. Assume that both Tom and Sally can be replaced by spherical masses.

Answer 1

Hi there!

For this situation, we can use the following equation for gravitational force:

`F_g = (Gm_1m_2)/(r^2)`

Where:

G = Gravitational Constant (6.67 × 10⁻¹¹)

m₁ = Tom's mass (kg)

m₂ = Sally's mass (kg)

r = radius (m)

Plug in the given values:

`F_g = ((6.67*10^(-11))(75)(47))/(20^2) = \large\boxed{5.878 * 10^(-10) N}`