gravitational field

Which of the following is Newton's Law on Gravitation?

• F=Gm₁m₂/r
• F = Gm₁m₂/r²
• F = Gm₁m₂/2r
• F = m₁m₂/2r

How does the gravitational force the Earth exerts on the sun compare to the gravitational force the sun exerts on the Earth?

• The gravitational force the sun exerts on the Earth is larger

• The gravitational force the Earth exerts on the sun is larger

• Their gravitational forces are equal

• There is not enough information

Find the force due to gravity if the mass of the object is 2300 kg and the mass of the other object is 4000 kg. The distance between the two objects is 0.150 m.

• 4.09 x 10^-3 N

• 244 N

• 2.7 x 10^-2 N

• 6.14 x 10^-4 N

If you double the mass of both m1 and m2, by what factor will the gravitational force change?

• F/4
• 4F
• 16F
• F/16

A body of mass 20 kg mass is placed 4 m

above the Earth's surface. The value of g

may be taken as lOms^-2 . What are the gravitational field strength and gravitational force acting on the body?

• A

• B

• C

• D

a ball with mass 2.5kg. what is the weight of the ball?

• 24.5 N

• 2.5 kg

• 2.5N

• 24.5kg

if the gravitational acceleration for the moon 1/6 g of the gravitational acceleration of the earth. If the weight of the object on earth 120N . How much the object weight in the moon?

• 120N

• 20N

• 196.2 N

• 720N

What is the acceleration due to free fall when the distance is twice the radius of the Earth?

• 4g

• g

• g/4

• g/2

Saturn’s average distance from the Sun is 9.6 AU (or 1.43 x 1012 m). Calculate Saturn’s orbital period using two methods: Newton’s law of universal gravitation and Kepler’s third law. ( Note the mass of the sun is 1.99 x10³⁰ kg and the Q= 6.67x10^-11 Nm² /kg²

• 10.78 days

• 10500 days

• 107 days

• 10785 days

Two satellites orbit the earth . Satellite A is 100km above the earth ground, Satellite B 200km above the ground . Which satellite moves faster, and which one has the longest  orbital period?

• the faster is A. the longest orbital period is for B

• the faster is B. the longest orbital period is for A

• the faster and has the longest orbital period is B

• the faster and has the longest orbital period is B