Physics – Class 11 Practice Test 7

1. What does the area under the stress-strain curve represent?

Modulus of elasticity

Total deformation

Average force applied

Toughness

2. Consider two satellites A and B. Both move around the earth in the same orbit but the mass of B is twice that of the mass of A.

The orbital speed of B is twice that of A

The orbital speed of A is twice that of B

The kinetic energy of both A and B are equal

Orbital speeds of A and B are equal

3. From which of the following is the working of hydraulic machines based on?

Ideal Gas Law

Pascal’s Law

Law of Gravitation

Newton’s Law of Cooling

4. A satellite is revolving very close to a planet of density D. What is the time period of that satellite?

[(3*G)/D]^1/2

[3/(D*G)]^1/2

[3/(2*D*G)]^1/2

[3/(D*G)]^3/2

5. A satellite of mass “m” is in a circular orbit of radius 1.5R around the earth of radius R. How much energy is required to move it to an orbit of radius 2R?

-(G*M*m)/4R

-(G*M*m)/12R

(G*M*m)/4R

(G*M*m)/12R

6. A satellite is launched into a circular orbit of radius R while a second satellite is launched into an orbit of radius 1.02R. What is the percentage change in the time periods of the two satellites?

0.7

1.5

7. Select the correct option. B is bulk modulus.

B_solid > B_liquid > B_gas

B_liquid > B_gas> B_solid

B_liquid > B_gas > B_solid

B_gas > B_liquid > B_solid

8. For a satellite with an elliptical orbit and not a circular orbit, the potential energy varies with time.

True

False

9. A wire has a cross sectional area ‘A’, length ‘L’ and young’s modulus ‘Y’. It is pulled by a force ‘F’ which causes a total extension of length ‘l’. The force F is so adjusted that the wire is only slowly stretched. Find the work done by the force in pulling the string by a length ‘dx’ when extension is x (0 > x > l).

(AY/L)xdx

½*stress * strain

½*stress*strain*volume

F*l

10. What is Pascal’s Law?

A pressure change at any point in the fluid is transmitted throughout the fluid such that the same change occurs everywhere

For an ideal gas, the pressure is directly proportional to temperature and constant volume and mass

For every action, there is an equal and opposite reaction

Force is the time rate of change of momentum