Siphoning

Q. State two examples to show that air exerts pressure. [2 MARKS]

Q.

A drinking straw works on the existence of ____________pressure.

Q.

Holes are made in hanging banners and hoardings. Explain?

Q.

Syringes are used to take blood for blood samples. The pressure of the blood forces the liquid to move into the syringe when the plunger is withdrawn.

1. True

2. False

Q.

A paper ball is kept at the mouth of a plastic bottle. When the bottle is compressed by hand, the paper ball will be pushed out. This is because:

1. the air pressure inside the bottle is same as that at its mouth

2. the air pressure inside the bottle is more than the pressure at its mouth

3. the air pressure inside the bottle is less than that at its mouth

4. the pressure is same in the bottle and outside it

Q.

When the mouth of an inflated balloon is left open, the entire air that was blown into the balloon escapes. This is because of ____.

1. the air inside it was hot.

2. air pressure difference

3. the air inside it was cold.

4. the acceleration due to gravity.

Q.

Boyle’s law states that at constant temperature, if pressure is increased on a gas, Volume decreases and vice-versa. But when we fill air in a balloon, volume as well as pressure increase. Why?

Q.

What happens to the shape of a thin hot tin can if it is closed and cold water is poured on it?

1. Pressure inside the can is less than that outside, so it shrinks.

2. Pressure inside the can is more than that outside, so it shrinks.

3. Pressure outside the can is same as that inside, so the shape remains the same.

4. Pressure inside the can is equal to the atmospheric pressure - final shape depends on the atmospheric pressure.

Q. Question 3
State two examples to show that air exerts pressure.

Q. Desrcible an activity that air exerts pressure ?

Q.

Find examples of use of fluid pressure.

1. Cooking in pressure cooker.
   
2. Blood test using Syringe
3. Lifting a car
4. Applying Brake of a car

Q.

Siphoning is due to the difference in weight of the water columns of the "U" shaped tube.

1. True

2. False

Q.

Pick out the options which work on the same working principle as that of the given device.

1. A straw

2. Pressure gauge

3. A syringe

4. An ink dropper

Q. State an experience that made you think that air exerts pressure. [1 MARK]

Q.

In a functional siphon, water rushes from the reservoir to the siphon because____.

1. the pressure in siphon is higher than atmospheric pressure.

2. the pressure in siphon is lower than atmospheric pressure.

3. pressure has no role in the phenomena.

4. the pressure in siphon is zero.

Q.

Aneroid barometer can be used to measure very minute changes in pressure.

1. False

2. True

Q. Holes are made in the banners and hoardings. Give reasons.[3 MARKS]

Q. Desrcible an activity that air exerts pressure ?

Q.

When we will put a transparent bottle in hot water, what type of pressure is build in it?

Q. In a functional siphon, water rushes from the reservoir to the siphon because ______ .

1. the pressure in siphon is higher than the atmospheric pressure
2. the pressure in siphon is zero
3. the pressure in siphon becomes equal to the atmospheric pressure
4. the pressure in siphon is lower than the atmospheric pressure

Q.

The pressure inside the bottle increases when the bottle is pressed and released.

1. True

2. False

Q. The flow of water from the taps to overhead tanks, in our homes is an application of siphoning.

1. False
2. True

Q. Siphoning works on the principle of pressure difference.

1. False
2. True

Q. When cold water is poured over a tightly corked tin can containing steam, the tin can gets crushed. What crushes the tin can?

Q.

Select the incorrect statement(s).

1. A siphon generally uses gravity to function.

2. A siphon works only for water.

3. A siphon can work in vacuum as well.

4. A siphon does not require any external force to function.

Q.

Identify the device which is shown below.

1. Siphon

2. Sphygmomanometer

3. Barometer

4. Pressure gauge