C3 Gravitation

Calculate the gravitational force between a 15 kg chinchilla and a 65 kg dog which are separated by 0.30 m.

Given G = 6.67x10^-11 N m² kg^-2.

• F_g = 3.7x10^-8 N

• F_g = 1.3x10¹² N

• F_g = 1.1x10⁵ N

• F_g = 7.2x10^-7 N

What would the gravitational force be between the Sun and Mars if they were 2.3 x 10¹¹ m apart? The masses for the Sun and Jupiter are 1.99 x 10³⁰ kg and 6.42 x 10²³kg, respectively. Given G = 6.67x10^-11 N m² kg^-2.

• F_g = 3.8 x 10¹⁵ N

• F_g = 2.8 x 10^-42 N

• F_g = 1.6 x 10²¹ N

• F_g = 4.6 x 10^-75 N

Given the mass of the earth is 5.97x10²⁴ kg, radius of the earth is 6.37x10⁶ m, G = 6.67x10^-11 N m² kg^-2. Calculate the gravitational acceleration of object B at 400 km height from the surface of the earth.

• 8.00 N kg^-1

• 8.23 N kg^-1

• 8.57 N kg^-1

• 8.69 N kg^-1

What happen to the gravitational acceleration to an object if the object is moving from surface of the planets to the outer space?

• increases

• decreases

• unchanged

• increase, then decrease

There is a car moves in a circle. Which of the following can explain the above situation?

• There is a force acts in opposite direction with car's weight.

• There is a force acts as centripetal force towards the centre of circle.

• There is a force acts in the direction of movement.

• There is a force acts away from the centre of circle.

A man-made satellite move orbiting the earth at 265 km height from the surface of the earth with speed 4000 m s^-1. What is the centripetal acceleration while its orbiting the earth? Radius of the earth is 6.37x10⁶ m, G = 6.67x10^-11 N m² kg^-2.

• 2.4 m s^-2

• 2.5 m s^-2

• 50.5 m s^-2

• 60.4 m s^-2

The diagram shows planer Jupiter and Venus are orbiting the Sun with R1 and R2 respectively. What is the ratio of orbital period planet Jupiter and Venus if the ratio of radius orbit planet Jupiter and Venus is 9: 4?

• 64: 729

• 16: 81

• 27: 8

• 8: 27

Which of the following is true about geostationary satellite?

• Above different geographical location.

• The orbital period is longer than 24 hours.

• It does not experience any gravitational pull

• Its period of rotation is one day.

Given the radius of the moon is 1740 km, the mass of the moon is 7.35x10²² kg and G = 6.67x10^-11 N m² kg^-2, find the escape velocity from the moon.

• 2374 m s^-1

• 2300 m s^-1

• 1679 m s-1

• 75067 m s-1

• 9996 ms^-1

• 9996 ms^-2

• 9000 ms^-1

• 9000 ms^-1