Earth's Gravitational Acceleration

Q.

An object is thrown vertically upwards to a height of $10\mathrm{m}$.

i. Calculate its velocity with which it was thrown upward.

ii. Calculate its time taken by the object to reach the highest point.

Q. Which of the following statement(s) is/are correct?

Statement 1: Mass of a body is defined as the quantity of matter contained in it.
Statement 2: Mass of a body remains constant and does not change from place to place.
Statement 3: Mass of a body can not be zero.
Statement 4: Unit of mass is Newton.

1. Only statements 1 and 2 are correct.
2. Only statement 1 is correct.
3. ​Only statements 3 and 4 are correct.
4. Only statements 1, 2 and 3 are correct .

Q.

To estimate the height of a bridge over a river, a stone is dropped from the bridge. It takes $3seconds$to touch the surface of water. Calculate the height of the bridge. [ Take $g=9.8m{s}^{-2}$]

Q.

A body is thrown up with an initial velocity of $10m{s}^{-1}$. It reaches a maximum height, $h$. Find the value of $h$. [Take acceleration due to gravity, $g=10m{s}^{-2}$]

1. $10m$

2. $15m$

3. $20m$

4. $5m$

Q.

At the centre of the earth, mass of body is zero.

1. True
2. False

Q.

Which of the following statements is correct?

Statement 1: Mass of a body is defined as the quantity of matter contained in it.
Statement 2: Mass of a body remains constant and does not change from place to place.
Statement 3: Mass of a body cannot be zero.
Statement 4: Unit of mass is kg.

1. Only statement 1 is correct

2. ​Only statement 3 and 4 are correct

3. Only statement 1 and 2 are correct

4. All statements are correct

Q. Brandon Stark saw some suspicious activity at the terrace of a tower. When he reached there, he saw some thieves and hurried back to tell his father. Accidentally, he fell from the top of the tower and landed on the ground exactly 2 seconds later. Find the height of the tower. $g=10m{s}^{-2}$

1. 5 m

2. 10 m

3. 15 m

4. 20 m

Q.

The weight of an object reduces by a factor of 4 as it is taken from the earths surface to a height of 6400km. Determine the earths radius.

Q. A fruit is dropped from a height of 20 m. Find the velocity with which it would hit the ground.

1. $40m{s}^{-1}$
2. $50m{s}^{-1}$
3. $20m{s}^{-1}$
4. $30m{s}^{-1}$

Q. Wont i become mass less fr some time if it happens .....
i know that without mass i cant posses energy... But then also?

Q.

Two planets of radii $r_1$ and $r_2$ ​are made from the same material. The ratio of the acceleration due to gravity $\frac{g_1}{g_2}$​ at the surface of the two planets is:

1. ​

2. ​

3. ​

4. ​

Q. A ball is thrown upwards with a velocity of $10m{s}^{-1}$. Find the maximum height reached by the ball.

1. $13m$
2. $5m$
3. $15m$
4. $16m$

Q. The value of $g$ at a particular point on the earth surface is $9.8m{s}^{-2}$. Suppose the earth suddenly shrinks uniformly to half its present size without losing any mass. The value of ‘g’ at the same point (assuming that the distance of the point from the centre of earth does not shrink) will now be:

1. $19.6m{s}^{-2}$
2. $4.9m{s}^{-2}$
3. $3.1m{s}^{-2}$
4. $9.8m{s}^{-2}$

Q. A ball is thrown upwards with an initial velocity of $20m{s}^{-1}$. Find the time of flight and the maximum height reached by the body respectively. ($g=10m{s}^{-2}$)

1. $5s$
   $25m$
2. $4s$
   $20m$
3. $4s$
   $24m$
4. $5s$
   $30m$

Q.

If $g$ is acceleration due to gravity, then the vertical distance traveled by a projectile in time t is equal to

1. $\frac{1}{2}g{t}^2$

2. $g{t}^2$

3. $\frac{3}{4}g{t}^2$

4. none of these

Q. A stone is dropped from a bridge and it reaches the ground in $4$ seconds. The height of the bridge is

1. $78.4\text{m}$
2. $64.2\text{m}$
3. $98.6\text{m}$
4. $116.8\text{m}$

Q. ntThe reduced mass of two particles having masses m and 2m is ?n

Q.

If we drop three watermelons weighing $2kg$, $4kg$ and $6kg$ respectively from the same height and at the same time, which one of it will reach the ground first? (Given: negligible air resistance)

1. Watermelon weighing $6kg$

2. All three will reach at the same instant.

3. Watermelon weighing $2kg$

4. Watermelon weighing $4kg$

Q.

What is the value of acceleration due to gravity of the Earth?
(Given mass of the Earth is $6\times {10}^{24}kg$ and radius of the Earth is $6.4\times$ ${10}^{6}m$).

1. $9.8m{s}^{-2}$
2. $9.8cm{s}^{-2}$
3. $9.8mm{s}^{-2}$
4. $9.8km{s}^{-2}$

Q. Suppose a quantity x can be dimensionally represented in terms of M, L and T, that is, . The quantity mass
(a) can always be dimensionally represented in terms of L, T and x,
(b) can never be dimensionally represented in terms of L, T and x,
(c) may be represented in terms of L, T and x if a = 0,
(d) may be represented in terms of L, T and x if .