Acceleration Due to Gravity

Q.

Give the S.I. unit of G and its value.

Q. Question 8
What is the acceleration of free fall?

Q. Assertion: The value of ‘g’ decreases as height increases from the surface of Earth.
Reason: ‘g’ depends on the mass of Earth.

1. Both the assertion and the reason are true, but the reason is not the correct explanation of the assertion.
2. Both the assertion and the reason are true and the reason is the correct explanation of assertion.
3. Assertion is true, but the reason is false.
4. Assertion is false, but the reason is true

Q.

Kamini hired a taxi and noted the initial reading of its odometer as $24803km$. After the journey, she noted the final reading of odometer as $25118km$. If the journey time was $4hours40minutes$, calculate the average speed of the taxi during the entire journey.

Q. The velocity of a freely falling body, starting at rest and after one second is___.

1. $10m{s}^{-1}$
2. $100m{s}^{-1}$
3. $15m{s}^{-1}$
4. $98m{s}^{-1}$

Q.

The gravitational force between sun and jupiter is approximately $4\times {10}^{23}$N. If mass of sun = $1.99\times {10}^{30}\mathrm{kg}$, the mean distance of the jupiter from the sun is $7.8\times {10}^{11}\mathrm{m}$, find the mass of jupiter.

Q.

Define acceleration due to gravity. Deduce an expression for it in terms of the mass of the earth (M) and the universal gravitational constant ‘G’.

Q.

The value of quantity G in the law of gravitation

1. depends on the mass of the earth only

2. depends on the radius of the earth only

3. depends on both the mass and radius of the earth

4. is independent of the mass and radius of the earth

Q.

If the density of the planet is increased, then the acceleration due to gravity at its surface will _____________

Q.

Equation of motion for free fall can be used in case of any free fall.

1. True
2. False

Q.

Give an expression for acceleration due to gravity.

Q.

What is the value of acceleration due to gravity on the moon?

($g$ is the acceleration due to gravity on the Earth)

1. 

2. 

3. 

4. can’t be determined

Q. An object is thrown vertically upward with a velocity of $10{\text{ms}}^{-1}$ from the ground. It strikes the ground after____ seconds. (Take $g=10{\text{ms}}^{-2})$

1. $10$
2. $5$
3. $2$
4. $1$

Q.

Compute the force of gravity on a body of mass $80kg$ lying on the surface of the earth. Given mass of the earth $6x{10}^{24}kg$, radius of the earth $6.4x{10}^{6}m$and $G=6.67X{10}^{-11}\frac{Nm²}{kg}$?

Q. Question 2
What do you mean by acceleration due to gravity?

Q. Two bodies of mass $10kg$ and $12kg$ are falling freely. What is the acceleration produced in the bodies due to the force of gravity?

1. Acceleration of both the bodies will be different
2. Acceleration of both the bodies will be same
3. Acceleration of both the bodies will be negative
4. Acceleration of both the bodies will depend upon friction

Q. A body of mass 2kg is hung on a spring balance mounted vertically in a lift . If the lift descends with an acceleration equal to the acceleration due to gravity 'g' , the reading on the spring balance will be
(A)2kg (B) (4×g)kg (C) (2×g)kg (D) Zero

Q. The radius of the earth is about $6400$ km and that of mars is $3200$ km. Thus mars of the earth are about $10$ times the mass of mars. An object weighs $200N$ on the surface of the earth. Then its weight on the surface of mars will be

1. $80N$
2. $40N$
3. $20N$
4. $8N$

Q.

Acceleration due to gravity 'g' in terms of mean density of the Earth 'd' and radius 'R' is:

(G is universal gravitational constant)

1. 4​dG

2. 

3. RdG

4. 

Q. The density of earth in terms of acceleration due to gravity (g), radius of earth (R) and universal gravitational constant (G) is:

1. $\frac{4\pi RG}{3g}$
2. $\frac{3\pi RG}{4g}$
3. $\frac{4G}{3\pi RG}$
4. $\frac{3g}{4\pi R^{2}G}$

Q.

A truck has a mass of 1600 kg. If the truck has to be stopped with a negative acceleration of 1.8 ms^-2. What is the force of friction between the truck and the road? (Give your answer in N)

___

Q.

Acceleration due to gravity 'g' in terms of mean density of the Earth, 'd ' (where R is radius of the Earth and G is universal gravitational constant) is

1. 4/3πRdG

2. 4πr²dG

3. 4πr²/G

4. 3/4πRdG

Q. If the radius of the Earth were increased by a factor of $2$ and its mass remained the same, then the acceleration due to gravity on the Earth would

1. reduce by factor $4$
2. reduce by factor $2$
3. not change
4. none of the above

Q.

Suppose you are on a roller coaster ride that is undergoing free fall. If you release a ball, from your perspective what can you say about the motion of the ball?

1. The ball does not appear to move.

2. The ball will move slowly.

3. Can't say

4. The ball will move reversely.

Q. The value of g at the center of the earth is zero. What will be the weight of a body of mass m kg at the center of the earth?

Q. A man can swim at 4m/s in a still water swimming pool. He enters a 200m wide river at one bank and swims (w.r.t. water) at an angle of 60 degree to the river flow velocity. The river flow velocity 5m/s. In how much time does he cross the river Calculate his drift

Q.

An apple that falls from a tree is an example of:

1. Contact Force

2. Non-Contact Force

3. Magnetic Force

4. Normal Force

Q. The ratio of radii of the earth to another planet is $\frac{2}{3}$ and the ratio of their mean densities is $\frac{4}{5}$. If an astronaut can jump to a maximum height of $1.5m$ on the earth, with the same effort, the maximum height he can jump on the planet is

1. $1m$
2. $0.8m$
3. $0.5m$
4. $1.25m$

Q. Find the velocity of the ball when it is at the height of 105 m while coming down.

1. 0 m/s
2. 4 m/s
3. 8 m/s
4. 40 m/s

Q.

A box of weight 50 kg rests on the surface of a lift. If the lift begins to fall freely under gravity, what is the force with which the box applies force on the surface?