Physics – Class 11 Mock Test 8

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Question 1 of 10

1. Choose the correct option regarding a streamline.

Speed, not velocity, at all points of a streamline is same

In a given streamline, velocity of a point can vary with time

There is no friction between streamlines in case of steady flow

Two streamlines can intersect in case of laminar flow

Question 1 of 10

Question 2 of 10

2. What is the effect of temperature increase on viscosity of liquids and gases?

Increases for both liquids and gases

Increases for liquids and decreases for gases

Increases for gases and decreases for liquids

Decreases for both liquids and gases

Question 2 of 10

Question 3 of 10

3. What is the unit of coefficient of viscosity?

Ns/m

Nm/s

Nm/s²

Ns/m²

Question 3 of 10

Question 4 of 10

4. It is possible that with decrease in temperature volume may increase. True or False?

False

True

Question 4 of 10

Question 5 of 10

5. A steel and a copper bar are joined end to end. The area of the steel bar is half the area of the copper bar. Their lengths are equal to 10cm each. Temperature of free ends of steel & copper rod are 0°C & 100°C respectively. K_S = 50 J/smK & K_C =384 J/smK. Calculate equivalent thermal conductivity of the combined bar.

63°C

36K

63K

336°C

Question 5 of 10

Question 6 of 10

6. In a closed pipe of radius R, fluid (having some viscosity) is flowing laminarly. Which point along a cross section will have maximum speed?

R/2 from centre

Near the wall of pipe

Centre

All points will have same speed

Question 6 of 10

Question 7 of 10

7. A cylindrical tank of Height H has a hole on its side. It is kept on a flat surface. Assuming that hole’s area is much smaller than the area of the tank, what should be the distance of the hole below the top surface so that water coming out of the hole travels the maximum horizontal distance at the instant when the height of water is H?

H/3

H/2

same for all positions

Question 7 of 10

Question 8 of 10

8. What is the value of coefficient of volume expansion for an ideal gas?

1/3 * coefficient of linear expansion

2*coefficient of linear expansion

(V/ΔV)/ Δ T

(ΔV/V)/Δ T

Question 8 of 10

Question 9 of 10

9. Select the correct statement.

Convection involves heat transfer by vibration of particles at their position

Radiation doesn’t require any medium

Conduction involves movement of particles to transfer heat

Radiation is responsible for heat of gas flame heating the cooking pan

Question 9 of 10

Question 10 of 10

10. Select the correct statement for melting of any substance.

It occurs at the same temperature as that of vapourization

It is exothermic in nature

It occurs at 100°C

It requires heat to be supplied to the substance

Question 10 of 10