Question Text
Question 1 :
A ball weighing 4 kg of density $4000 kg m^{-3}$ is completely immersed in water of density $10^{3} kg m^{-3}$ Find the force of buoyancy on it. (Given $g = 10 m s^{-2}$)
Question 3 :
The mass of the earth is $6 \times 10^{24}$ kg and that of the moon is $7.4 \times 10^{22}]$ kg. If the distance between the earth and the moon is $3.84 \times 10^5$ km, What is the force exerted by the earth on the moon. (Take $G = 6.7 \times 10^{–11}\ N\ m^2\ kg^{-2}$)
Question 4 :
The motion of the moon around the earth is due to the _____________.
Question 6 :
A ball is thrown vertically upwards with a velocity of 49m/s. Calculate the maximum height to which it rises.
Question 7 :
A stone is thrown vertically upward with an initial velocity of 40 m/s. Taking g = 10 $m/s^2$,What is the net displacement and the total distance covered by the stone?
Question 9 :
Two objects of masses $ m_1$ and $m_2$ having the same size are dropped simultaneously from heights $ h_1$ and $h_2$ respectively. What will the ratio of time they would take in reaching the ground be if both of them are hollow, size remaining the same in each case?
Question 10 :
Relative density of silver is 10.8. The density of water is $10^3 \ kg/m^{3}$. What is the density of silver in SI unit?
Question 11 :
A boy is whirling a stone tied with a string in an horizontal circular path. If the string breaks, the stone :
Question 12 :
The density of an iron nail is _______ than the density of water
Question 13 :
How does the force of gravitation between two objects change when the distance between them is reduced to half ?
Question 14 :
In what direction does the buoyant force on an object immersed in a liquid act?