Question

Compare the weight of a 5.00-kg object on Earth’s surface to the gravitational force between a 5.00-kg object that is one Earth radius from another object of mass equal to 5.98 × 10 24 kg . Use Newton’s universal law of gravitation for the second part of the question

Answer 1

Answer

given,

mass of an object = 5 Kg

mass of the other object = 5.98 x 10²⁴ Kg

radius of earth = 6371 Km = 6.371 x 10⁶ m

comparison between gravitational force between two object and weight of the object.

gravitational force between two objects

   $F = \dfrac{Gm_1m_2}{r^2}$

   $F = \dfrac{6.67 \times 10^{-11}\times 5 \times 5.98 \times 10^{24}}{(6.371 \times 10^6)^2}$

      F = 49.134 N

weight of the object on the earth surface

  F = m g

  F = 5 x 9.81

  F = 49.05 N

From the above two calculation we can conclude that gravitational force is approximately equal to weight of the body.