Newton's Universal Law of Gravitation

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. 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.

One newton is that force which when acting on a body of mass 1 kg, produces an acceleration of

1. 1 cm s^-2 in the direction of force

2. 1 m s^-2 in the direction of force

3. 1 m s^-2 in the direction opposite to that of force

4. 1000 cm s^-2 in the direction of force

Q. If two bodies have a mass ratio of 1 : 2, what is the ratio of their accelerations due to gravitational force applied on each other?

1. 1 : 2
2. 2 : 3
3. 1 : 4
4. 2 : 1

Q.

Question 1
State the universal law of gravitation.

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.

Mass of a body is 50g and it is subjected to a force of 0.01 N. Calculate the acceleration of the body in SI units and CGS units.

1. 30 cms^-2

2. 20 cms^-2

3. 10 cms^-2

4. 50 cms^-2

5. 40 cms^-2

Q.

A force of 10 gf is applied on a body of mass 98g. Calculate the acceleration of the body [g = 9.8 m/s² = 980 cm/s²]

1. 50 cms^-2

2. 200 cms^-2

3. 250 cms^-2

4. 100 cms^-2

5. 150 cms^-2

Q. A force of 1 kg-wt acting on a mass of 9.8 kg produce an acceleration of ______

Q.

The force of gravitation between two bodies varies with $r$ as:

Q. Miranda, one of the moons of the planet Uranus, orbits the planet with an average speed of $6.5\text{km}{\text{s}}^{-1}$, while experiencing a centripetal force of $2\times {10}^{19}\text{N}$. What is the distance (in $\text{km}$) between Uranus and Miranda, if the moon has a mass of $6.4\times {10}^{19}\text{kg}$?

1. 135200

Q.

Give a mathematical expression for the gravitational force.

Q.

Which law is the basis of Newtons law of gravitation?

Q.

The external force for the earth-moon system is due to the?

Q.

What happens to the forces between two objects, if :
The masses of both objects are doubled?

Q. Question 5
If the moon attracts the earth, why does the earth not move towards the moon?

Q.

In a Searle's experiment, the diameter of the wire as measured by a screw gauge with least count 0.001 cm is 0.050 cm. The length, measured by a scale of least count 0.1 cm, is 110.0 cm. When a weight of 50 N is suspended from the wire, the extension is measured to be 0.125 cm by a micrometer of least count 0.001 cm. Find the maximum error in the measurement of Young's modulus of the material of the wire from these data.

$y=\frac{W}{A}\times \frac{L}{X}$
Where W is the weight suspended from the wire, A is the cross section area, L is the length and X is the extension in the wire.

1. 4.89 %

2. 1.26 %

3. 9.67 %

4. 15.56 %

Q. Question 6
What happens to the force between two objects, if

(i) the mass of one object is doubled?
(ii) the distance between the objects is doubled and tripled?
(iii) the masses of both objects are doubled?

Q. Question 18
Suppose gravity of earth suddenly becomes zero, then in which direction will the moon begin to move if no other celestial body affects it?

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.

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.

What is Gravitational Force?

Q.

suresh applied a force of 10N on a body to move it from rest.He wants to express the applied force in terms of kgf, then 10N is___________________?

Q. The mass of the sun is approximately $2\times {10}^{30}$kg. The Schwarzschild radius for the mass of a star that is ten times the mass of the sun is nearly

1. 3km
2. 30km
3. 300 km
4. 0.3km

Q. Write the three laws given by Kepler. How did they help Newton to arrive at the inverse square law of gravity?

Q. Ten grams of ${}^{60}Co$ kept in an open container $\beta$ decays with a half-life of 270 days. The decay products are constantly flushed out. The weight of the material inside the container after 540 days will be very nearly:

1. 10 g
2. 2.5 g
3. 1.25 g
4. 5 g

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. 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.

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

1. False
2. True