Question 1 :
Assertion: Pins and nails are made to have pointed ends in order to have the minimal area of contact between the pointed ends and the given surface.
Reason: Minimal area of contact means that the pressure applied on the surface by the pin is greater.
Question 2 :
The upward force exerted by the floating body on the fluid is known as upthrust.
Question 5 :
Mass of moon is $7.34\times 10^{22}kg$. If the acceleration due to gravity on the moon is $1.4 ms^{-2}$, the radius of the moon is: $[G=6.667\times 10^{-11} N m^2 kg^{-2}]$
Question 6 :
If M is the mass of the earth and R its radius, the ratio of the gravitational acceleration and the gravitational constant is given by:<br/>
Question 7 :
When the weight of a given body is more than the weight of the fluid displaced by it, the body:
Question 8 :
Name the force acting on a plastic bucket containingwater held above ground level in your hand. <br>
Question 9 :
What is the mass of an object whose weight is 98 N?
Question 10 :
State whether given statement is True or False<br/>Because the buoyant force acts in a direction opposite the force of gravity, the net force acting on an object submerged in a fluid, such as water, is smaller than the object's weight.<br/>
Question 11 :
The weight of an object of mass $1 \,kg$ is equal to:
Question 12 :
If the density of a metal is $8.2 {g}/{cc}$, its relative density is
Question 13 :
A block of wood weights 12 kg and has a relative density 0.6. It is to be of its volume immersed. What weight of a metal is needed if the metal is on the top of wood? [Relative density of metal = 14].
Question 14 :
Relative density of a body wrt a medium of density $\rho_1$ is a. What is the relative density of the body wrt a medium of density $\rho_2$
Question 16 :
Assertion: A balloon filled with hydrogen will fall with acceleration $\displaystyle\frac{g}{6}$ on the moon.
Reason: Moon has no atmosphere.
Question 17 :
Two balls are dropped from the same height from places $A$ and $B$. The body at $B$ takes two seconds less to reach the ground at $B$ strikes the ground with a velocity greater than at $A$ by $10 m/s$. The product of the acceleration due to gravity at the two places $A$ and $B$ is:
Question 18 :
Assertion: A block of wood is floating in a pond of water and its apparent weigth is zero.
Reason: The weight of water displaced (buoyant force) acting vertically upwards is just equal to the weight of the body which acts vertically downwards.
Question 19 :
Two spherical bodies of mass $M$ and $5M$ and radii $R$ and $2R$ respectively are released in free space with initial separation between their centres equal to $12 R$. If they attract each other due to gravitational force only, then the distance covered by the smaller body just before collision is