# Gravitational Force questions

#### MCorporal

Questions;

1. Calculate the gravitational force between two 50 kg objects if they are 7.5 x 10^-1 m apart?

2. the gravitational force between two objects are 2.1 x 10^-1 m apart is 3.2 x 10^-6 N. if the mass of one object is 55 kg, what is the mass of the other object?

3. Two students are sitting 1.5 m apart. one student has a mass of 70 kg and the other 52 kg. what is the gravitational force between them?

4. if two objects, each with a mass of 2 x 10^2, produces a gravitational force between of 3.7 x 10^-6, what is the distance between them?

5. on the surface of planet X an object has a weight of 63.5 N and a mass of 22.5 kg. what is the acceleration due to gravity on the surface of planet X?

6. Jupiter is the largest planet in the solar system. it has a mass of 1.9 x 10^27 kg and a radius of 7.18 x 10^7 m. What is the acceleration due to gravityof an object near jupiters surface?

7. If two objects with a mass of 215 kg, produce a gravitational force between them of 5.3 x 10^-6 N, what is the distance between them?

These are questions that I'm confused with, and can't seem to get a right answer.

Thank you

#### Pythagorean

##### excitation
Gold Member
This seem like they can all be answered using one general equation. Do you have an idea of what that equation is?

#### jdwood983

These are all related to the same equation:

$$F=G\frac{m_1m_2}{r^2}$$

where G is the gravitational constant: $G=6.67\times10^{-11}$ m3kg-1s-2. Each question uses this formula, though questions 5 and 6 require further that $F=ma$.

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