Universal Law of Gravitation

Q.

What is the value of G in force of an gravity

Q.

If the distance between the Earth and the Sun were half its present value, the approximate number of days in a year on the Earth would have been:

1. $182.5days$

2. $129days$

3. $64.5days$

4. $730days$

Q.

All the planets move around the sun in a

1. Circular path

2. Rectangular path

3. Elongated path

Q.

Two spheres of masses m and M are situated in air and the gravitational force between them is F. The soace around the masses are now filled with a liquid of specific gravity 3. The gravitational force will now be:

F/3

F/9

3F

F

Q. The $SI$ unit of universal gravitational constant is:

1. $N{m}^{2}k{g}^{-2}$
2. $N{m}^{-2}k{g}^2$
3. $N{m}^{2}k{g}^2$
4. $N{m}^{-2}k{g}^{-2}$

Q.

The value of gravitational constant, $G$ is

1. $9.8m{s}^{-2}$

2. $6.7N$

3. $6.7\times {10}^{-11}N{m}^{2}k{g}^{-2}$

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

Q.

Define universal gravitational constant. Does the value of G change with a change in mass and distance?

Q.

A body weighs $72N$ on the surface of the earth. What will be the force of gravity acting on the body at a height equal to half the radius of the earth above the earth's surface?

1. 0

2. $20N$

3. $10N$

4. $32N$

Q. Applications of Newton's first law, second law and third law of motion. (10 for each law)

Q.

Question 3
What is the magnitude of the gravitational force between the earth and a 1 kg object on its surface? (Mass of the earth is $6\times {10}^{24}kg$ and radius of the earth is $6.4\times {10}^{6}m$)

Q. explain the difference in weight when an object is in moon and earth

Q.

A solid sphere of mass $M$ and radius $R$ has a spherical cavity of radius $\frac{R}{2}$ such that the centre of the cavity is at a distance of $\frac{R}{2}$ from the centre of the sphere. A point mass $m$ is placed inside the cavity at a distance of $\frac{R}{4}$ from the centre of the sphere. The gravitational pull between the sphere and the point mass $m$ is

1. $\frac{11GMm}{R^2}$

2. $\frac{14GMm}{R^2}$

3. $\frac{GMm}{2R^2}$

4. $\frac{GMm}{R^2}$

Q.

Write the mathematical equation for Newtons law of gravitation.

Q.

Write the formula to find the magnitude of the gravitational force between the earth and an object on the surface of the earth. [2 MARKS]

Q. Value of Gravitational constant G on moon

Q.

Why is the gravitational law called the universal law of gravitation?

Q.

The mass density of a planet of radius$R$ varies with the distance$r$ from its center as$\rho \left(r\right)={\rho }_0(1-(r^2/R^2\left)\right)$. Then the gravitational field is maximum at:

1. $r=1/\surd 3R$

2. $r=(\surd 3/\surd 4)R$

3. $r=R$

4. $r=(\surd 5/\surd 9)R$

Q. What is the SI unit of gravitational constant?

1. $N{m}^{-2}K{g}^{-2}$
2. $N{m}^{3}K{g}^2$
3. $N{m}^{2}K{g}^{-2}$
4. $NmK{g}^{-2}$

Q.

How to prove $1gf=980dyne$?

Q. If the masses of two objects are doubled, and the distance between them is halved, then the gravitational force acting between them becomes

1. 4 times as before
2. 2 times as before
3. 16 times as before
4. 3 times as before

Q.

What is the realation between small g and capital G

Q.

Apple falls towards the earth but the earth does not move towards the apple because

1. acceleration is inversely proportional to mass, so acceleration of earth is negligible

2. only earth exerts force on apple, apple does not exert force on earth

3. apple experiences greater force than the earth

4. only apple exerts force on earth, earth does not exert force on apple

Q.

The mass of sun is $2\times {10}^{30}$ kg and the mass of earth is $6\times {10}^{24}$ kg. If the average distance between the sun and the earth be $1.5\times {10}^8$km, calculate the force of gravitation between them.

Q.

Given mass of earth is 6 × ${10}^{24}$ kg and mean radius of earth is 6.4 × ${10}^6$ m. Calculate the value of acceleration due to gravity (g) on the surface of the earth.

Q. What is gravitational constant?

Q.

Infinite number of masses each $1kg$ are placed along the $X–axisatx=\pm lm,\pm 2m,\pm 4m,\pm 8m,\pm 16m...$. The magnitude of the resultant gravitational potential in terms of gravitational constant$G$ at the origin $(x=0)$ is

1. $\frac{G}{2}$

2. $G$

3. $2G$

4. $4G$

5. $8G$

Q. The gravitational force between two objects is $F$. If both of their masses are halved without altering the distance between them, the new gravitational force between them would be:

1. $\frac{F}{4}$
2. $2F$
3. $\frac{F}{2}$
4. $4F$

Q. All the values and formulas from lesson gravitation

Q.

What is the range of gravitational force?

Q. Which of the following is responsible for keeping a satellite in orbit?

1. centripetal force
2. frictional force
3. gravitational force of the earth
4. circular motion