Law of Floatation

Q. Why does the pressure of liquids increases with depth?
What is the possible scientific reason for this?

Q.

What is the law of floating? [2 Marks]

Q.

What do you mean by buoyancy?

Q.

What is acceleration due to gravity on Jupiter?

Q.

It is easier for a person to swim in sea water than in river water. The reason is that:

1. the density of sea water is more than the density of river water.

2. sea water is lighter than the river water.

3. the density of sea water is less than the density of river water.

4. sea water is heavier than the river water.

Q.

State the relation between cubic meter and liter

Q.

Why water bubbles are spherical in shape?

Q. Warm air rises. What is the reason for this? [2 MARKS]

Q. What is the difference between mass and density ? How the two objects have same mass even though they differ in density ? Can you explain it detailed ?

Q. what is rarefraction

Q.

The density of water varies with temperature. What are its consequences?

Q.

A balloon filled with helium gas rises up. Give reason.

Q.

Oil floats on water because oil is more dense than water.

1. True
2. False

Q.

The volume of water displaced by the object gives___.

1. weight of the submerged part of the object

2. weight of the entire object

3. density of the submerged part of the object

4. density of the entire object

Q.

Calculate the apparent weight of a stone whose weight in the air is 250 g and the upthrust is 0.8 N.$(takeg=9.8m{s}^{-}2)$

1. 16.5 N

2. 1.65 N

3. 1.56 N

4. 0.165 N

Q. A body floats in water with 40% of its volume outside water. When this body is kept in oil, it
floats with 60% of its volume remains outside the oil. The relative density of oil is
k/2
Find value
of K.

Q.

What is the pressure of the water column whose height=10CM density=20kg gravity=9.8

Q.

Icebergs floating on seawater are dangerous for ships. Explain the reason.

Q.

The gravitational force $Fg$ between two objects does not depend on

1. Sum of the masses

2. Product of the masses

3. Gravitational constant

4. Distance between the masses

Q.

Write applications of Archimedes principle.

Q.

Density of a body depends on its shape and size

Q.

We know that I've floats on Water because it is lighter. Can ice sink in any other liquid such as kerosene oil? State the condition under which ice sink in other liquid.

Q. An iron nail sinks in water but a ship made from iron floats in water. Why?

1. The weight of the nail is more than the upthrust experienced by it
2. The average density of the ship is less than the density of water
3. Both A & B
4. Unsure

Q.

What are the applications of Archimedes principle?

1. It is used in designing of ship and submarines

2. All of the above

3. In lactometers, to determine the purity of milk

4. In hydrometers to determine density of fluids

Q.

Answer the following in one statement:

A piece of iron sinks in the water while a wooden piece floats. Why is it so?

Q.

When the distance between two bodies of masses $m_1$ and $m_2$ is doubled, then the gravitational force between them is _________ of the initial gravitational force.

1. $\frac{1}{4}th$

2. $\frac{1}{5}th$

3. 4 times

4. twice

Q. An iron needle sinks in water but floats on mercury of density.Give reason

Q.

The apparent weight of the floating body is zero.

1. True

2. False

Q.

If two spheres of same materials immersed in water experience unequal upthrust, then which of the following statements is/are true?

1. Their volumes inside the water are equal.

2. Their loss of weights in water are equal.

3. Their volumes inside the water are unequal.

4. Both (a) and (c)

Q.

The density of an object can be varied by changing its shape.

1. True
2. False