Acceleration due to Gravity

Q.

Derive an expression for acceleration due to gravity.

Q.

Calculate acceleration due to gravity at a height of $2000km$ above the Earth's surface. Mass of Earth = $6\times {10}^{24}kg$, radius of Earth = $6.4\times {10}^6$ m and (Gravitational constant, G $=6.7\times {10}^{-11}N{m}^{2}k{g}^{-2}$)

1. $5.7m{s}^{-2}$

2. $3.7m{s}^{-2}$

3. $6.7m{s}^{-2}$

4. $4.7m{s}^{-2}$

Q. What is the value of acceleration due to gravity for a body moving against gravity if its velocity is positive?

1. $9.8m{s}^{-2}$
2. Zero
3. $19.6m{s}^2$
4. $-9.8m{s}^{-2}$

Q.

A boy while playing under a mango tree saw a mango falling down. This is due to:

1. Gravitational force

2. Frictional force

3. Magnetic force

4. Nuclear force

Q.

What is the acceleration due to gravity if the mass of the earth is $6\times {10}^{24}kg$and its radius is $6400km?$

Q.

The mass and radius of a planet are eight times and two times the mass and radius of the Earth, respectively. Then, the acceleration due to gravity of the planet is _________ times the acceleration due to gravity on the Earth. (Take g = 10 m s^-2)

1. eight

2. four

3. two

4. three

Q. The velocity-time graph of a train traveling between two stations is plotted below:


Find the train's acceleration (in $\text{m}{\text{s}}^{-2}$) in each of the time intervals OX, XY, and YZ respectively.

1. $2,1,-4$
2. $-2,1,4$
3. $-2,0,4$
4. $2,0,-4$