11th class (Fsc) Physics unit 4 MCQs
chapter 4 MCQs 11th Class Physics
Work and Energy:
1. SI unit of work is:
a. Pascal
b. Newton
c. Joule
d. Walt
2. Work done will be maximum when angle between →F and →D is:
a. 60o
b. 180o
c. 0o
d. 90o
3. Work has dimension like:
a. Velocity
b. Torque
c. Power
d. Momentum
4. The work done is negative when angle between force and displacement is:
a. 0o
b. 45o
c. 180o
d. 90o
5. The dimensions of work are:
a. [ML2T-2]
b. [MLT-1]
c. [MLT]
d. [MLT-2]
6. The unit of work in base unit is:
a. Kg m2sec-2
b. Kg m-1sec-2
c. Kg m-1sec-1
d. Kg m2sec2
7. The P.E stored by a mass spring system at an extension of 2cm is 10J. the P.E stored by the same system at an extension of 4cm will be:
a. 30 J
b. 10 J
c. 40 J
d. 20 J
8. If work done is negative then the angle between force and displacement is:
a. 45o
b. Zero
c. Greater than 90o
d. 90o
9. Work has same dimensions as that of:
a. Momentum
b. Torque
c. Force
d. Power
10. The unit of work in base units is:
a. Kgm2sec-2
b. Kgm-1sec-2
c. Kgm-1sec-1
d. Kgmsec-2
11. If a body of mass 5kg is raised vertically through a distance of 1m. then work done is:
a. 490 J
b. 49 J
c. 0.49 J
d. 4.9 J
12. Which is non-conservative force:
a. Gravitational force
b. Electrical force
c. Frictional force
d. Magnetic force
13. Watt-m-2 is the unit of:
a. Power
b. Energy
c. Work
d. Intensity
14. Which one is a conservative force:
a. Air resistance
b. Elastic spring force
c. Tension in the spring
d. Frictional force
15. Identify the non-conservative force among the following:
a. Elastic spring force
b. Air resistance
c. Electric force
d. Gravitational force
16. The power needed to lift a mass of 5000 g to height of 1m in 2 seconds is:
a. 245 watt
b. 2.45 watt
c. 2.45 watt
d. 24.5 watt
17. Kilo watt hour is the unit of:
a. Force
b. Power
c. Torque
d. Energy
18. The commercial unit of electric energy is:
a. Watt-hour
b. Kilowatt hour
c. kilowatt
d. Watt
19. 3 joules of work is done in 3 seconds, then power is:
a. 18 Watt
b. 6 Watt
c. 1 Watt
d. 3 Watt
20. The dimension of power is:
a. [ML2T-2]
b. [MLT-1]
c. [ML2T-3]
d. [ML2T-2]
21. The escape velocity can be determined by relation:
a. Vesc = √gR
b. Vesc = gR
c. a. Vesc = √2gR
d. Vesc = 2gR
22. The escape velocity is maximum for:
a. Earth
b. Moon
c. Jupiter
d. Mercury
23. The value of escape velocity for earth is:
a. 1.1 km/h
b. 11 km/h
c. 1.1ms-1
d. 11kms-1
24. All the food we eat in one day has about the same energy as:
a. 1/3 liter of petrol
b. One liter of petrol
c. ¼ liter of petrol
d. ½ liter of petrol
25. Escape velocity of a body of mass 1000 kg is 11kms-1 . If the mass of the body is doubled then its escape velocity will be:
a. 22 kms-1
b. 5.5 kms-1
c. 44 kms-1
d. 11 kms-1