Newton's Universal Law of Gravitation

Q.

It is known that falling apple is attracted towards the Earth. We all know that the apple will also exert an equal and opposite force on the Earth. If so, we don’t observe Earth moving towards the apple, why?

1. Both are applying equal and opposite force on each other so it gets cancelled out.

2. The acceleration produced in the fruit in Earth would be very high.

3. No acceleration produced by the fruit in Earth.

4. The acceleration produced by the fruit in Earth would be negligible.

Q. Which of the following show(s) the importance of the universal law of gravitation?

1. The force that is responsible for binding us to the Earth.
2. The motion of the Moon around the Earth.
3. The motion of planets around the Sun.
4. When you fire a bullet, the gun recoils backward and the bullet is moving forward

Q. If the Earth shrinks half in radius and its mass remains the same, then by what percentage will the weight of an object on Earth change?

1. Decreases by $50\%$
2. Increases by $50\%$
3. Decreases by $25\%$
4. Increases by $300\%$

Q. Since the Moon has a force of gravity which is $6$ times lesser than Earth's, why doesn't it collapse into the Earth?

1. The Sun's gravitational force is greater than that of the Earth.
2. The mass of the Moon is less than that of the Earth.
3. Due to centripetal force which is the force of gravity exerted by the Earth on Moon.
4. The absence of gravity in space.

Q.

Newton's law of gravitation is applicable to:

1. Bodies on earth only

2. Bodies on planets other than earth

3. Bodies in our solar system only

4. All bodies in the universe

Q.

The value of gravitational constant, $G$ is

1. $6.7N$

2. $6.7\times {10}^{-11}N{m}^{2}k{g}^{-2}$

3. $9.8m{s}^{-2}$

4. $6.7\times {10}^{-11}N{m}^{2}k{g}^2$

Q. Gravitational force on increasing the distance between two bodies.

1. increases
2. decreases
3. remains same

Q. Suppose gravity of Earth suddenly becomes zero, then in which direction will the Moon begin to move if no other celestial body affects it?

1. The Moon will move in a straight line.
2. The Moon will not move at all.
3. The Moon will move in a curved line.
4. The Moon will continue its circular path.

Q. Consider a heavenly body which has a mass twice that of the Earth and radius thrice that of the Earth. What will be the weight of the book on this heavenly body, if its weight on the Earth is $900N$?

1. $600N$
2. $400N$
3. $200N$
4. $500N$

Q. Gravitational force between two bodies is inversely proportional to square of distance between them.

1. False
2. True