In a streamlined flow,
a. the speed of a particle always remains the same.
b. the velocity of a particle always remains the same.
c. the kinetic energies of all the particles arriving at a given point are the same.
d. the momenta of all the particles arriving at a given point are the same.
Choose the correct option:
1. (a) and (b)
2. (b) and (c)
3. (c) and (d)
4. All of these

Water flows through two identical tubes A and B. A volume V0 of water passes through the tube A and 2 V0 through B in a given time. Which of the following may be correct?

(a) Flow in both the tubes are steady.

(b) Flow in both the tubes are turbulent.

(c) Flow is steady in A but turbulent in B.

(d) Flow is steady in B but turbulent in A.

Choose the correct option:

1. (a), (b) and (c)

2. (b), (c) and (d)

3. (a) and (b)

4. (b) and (c)

Water is flowing in streamline motion through a tube with its axis horizontal. Consider two points A and B in the tube at the same horizontal level.

(a) The pressures at A and B are equal for any shape of the tube.

(b) The pressures are never equal.

(c) The pressures are equal if the tube has a uniform cross-section.

(d) The pressures may be equal even if the tube has a non–uniform cross-section.

Choose the correct option:

1. (a) and (b)

2. (b) and (c)

3. (c) and (d)

4. All of these

There is a small hole near the bottom of an open tank filled with a liquid. The speed of the water ejected does not depend on:

Choose the correct option:

By a surface of a liquid we mean

1. a geometrical plane like x = 0

2. all molecules exposed to the atmosphere

3. a layer of thickness of the order of 10^–8 m

4. a layer of thickness of the order of 10^–4 m

An ice cube is suspended in vacuum in a gravity-free hall. As the ice melts it

1. will retain its cubical shape

2. will change its shape to spherical

3. will fall down on the floor of the hall

4. will fly up

When water droplets merge to form a bigger drop:

Air is pushed into a soap bubble of radius r to double its radius. If the surface tension of the soap solution is S, the work done in the process is

1. 8 \(\pi\) r² S

2. 12 \(\pi\) r² S

3. 16 \(\pi\) r² S

4. 24 \(\pi\) r² S

If more air is pushed in a soap bubble, the pressure in it

1. decreases

2. increases

3. remains same

4. becomes zero

If two soap bubbles of different radii are connected by a tube,