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Work, Energy and Power
Monica G Sadhwani
ID No - 14162078
In this chapter you will come across
following terms
 Work
 Force
 Kinetic energy
 Potential Energy
 Mechanical energy
 Heat energy, chemical energy, Electrical
energy , Nuclear energy
 Power
Gist of Chapter
• What the chapter is about?
Let us start understanding what is
work??
 Work in Physics
Lets Test Our Brain
All the
Best
Instruction
 Just click on the answer you find correct
 Then you will be directed forward
 If you answer correctly you will move forward
 If your answer is wrong you will be directed towards concerned video or
file then make sure every time you go back and answer correctly and then
move forward
 Start here….
Q1.In case of negative work the angle between
the force and displacement is
(a) 00 °
(b) 450°
(c) 900 °
(d ) 180°
Watch the Video Again Attempt Again
Next Question
Q2. The work done on an object does not depend
upon the
(a) displacement
(b) force applied
(c) angle between force and displacement
(d) initial velocity of the object
Attempt Again
Q3. A body of mass 15 kg undergoes downward
displacement of 40 m under the effect of
gravitational force. Calculate work done (g = 10
m/s2
Acceleration a= g = 10 m/s2 , mass m = 15 kg
displacement s = 40 m
a)-6000 J
b) 6000 J
c) 600 J
d) 0 J
Attempt Again
Watch the Video
Again
Go Ahead
Q4. A body of mass 120 g is taken vertically
upwards to reach the height of 5m. Calculate
work done (g = 10 m/s2)
a) 6 J
b) 600 J
c) 0.6 J
d) - 6 J
Attempt Again
Next Question
Q5. Work done = Force x _______
a) distance
b) acceleration
c) velocity
d) speed
Next
Attempt Again
Watch the Video
Again
Q6. 1 joule = 1 _______
1. N m2
2. kg/m2
3. N m
4. N2 m2
Attempt Again
Move
Forward
Now Let Us Study about Energy
 Let us read something
Let Us Practice What we have
learnt about Energy…
Q7. A car is accelerated on a levelled road and
attains a velocity 4 times of its initial velocity. In
this process the potential energy of the car
(a) does not change
(b) becomes twice to that of initial
(c) becomes 4 times that of initial
(d) becomes 16 times that of initial
Lets
Read
Again
Now Try to
Answer
Next Question
Q8. Which one of the following is not the unit of
energy?
(a) joule
(b) newton metre
(c) kilowatt
(d) kilowatt hour
Lets
Read
Again
Q9. A body is falling from a height h. After it has
fallen a height h/2 , it will possess
(a) only potential energy
(b) only kinetic energy
(c) half potential and half kinetic energy
(d) more kinetic and less potential energy
Lets
Read
Again
Q10. When a body falls freely towards the earth,
then its total energy
(a) increases
(b) decreases
(c) remains constant
(d) first increases and then decreases
Lets
Read
Again
Q 11. Water stored in a dam possesses
(a) no energy
(b) electrical energy
(c) kinetic energy
(d) potential energy
Lets
Read
Again
Q 12. When a spring is compressed its potential
energy …….
a) Remains constant
b) Reduces
c) Increases
d) Nothing can be said about it
Lets
Read
Again
Q 13. A body of mass 10 kg performs motion
along a circle of radius 5m with speed of 10
m/s. Work done during one revolution is ......
(A)2000 J
(B)1000 J
(C)500 J
(D) zero
Lets
Read
Again
POWER
Lets watch video
Q14. 1 kWh= ........... J
(A)36 X 106
(B)3.6 X 106
(C) 3.6 X 107
(D) 3.6 X l05
Q 15.A boy of mass 40 kg climbs a staircase of
30 steps, each of 0.2m height, in 30 s. Calculate
power (g = 9.8 m/s2)
a. 8 W
b. 80 W
c. 18 W
d. 9 W
Q 16. Engine of a car of mass 1500 kg, keeps car
moving with constant velocity 5m/s. If
frictional force is 1000 N, power of engine is
...............
(A)5 kW
(B) 7.5 kW
(C)15 kW
(D) 75 kW
Q 17.Height of water dam in hydroelectric power
station is 20 m. How much water, in 1 second,
should fall on turbine, so that 1MW power is
generated ? (g = 10m/s2)
(A)5000 kg
(B)10,000 kg
(C)500 kg
(D)7,500 kg
Different Forms of Energy
Q 18.The law of conservation of energy is a
statement that
A) energy must be conserved and you are
breaking a law if you waste energy.
B) the supply of energy is limited so we must
conserve.
C) the total amount of energy is constant.
D) energy cannot be used faster than it is
created.
Q 19. The kinetic energy associated with the
random motion of the constituent particles of a
body, is known as
a) Heat Energy
b) Internal Energy
c) Nuclear Energy
d) None of the above
Q 20.Mass and energy are mutually
convertible according to the following relation
a) M= EC2
b) E = mc2
c) E = 1/2mc2
d) None of the above
PLM
PLM

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PLM

  • 1. Work, Energy and Power Monica G Sadhwani ID No - 14162078
  • 2. In this chapter you will come across following terms  Work  Force  Kinetic energy  Potential Energy  Mechanical energy  Heat energy, chemical energy, Electrical energy , Nuclear energy  Power
  • 3. Gist of Chapter • What the chapter is about?
  • 4. Let us start understanding what is work??  Work in Physics
  • 5. Lets Test Our Brain All the Best
  • 6. Instruction  Just click on the answer you find correct  Then you will be directed forward  If you answer correctly you will move forward  If your answer is wrong you will be directed towards concerned video or file then make sure every time you go back and answer correctly and then move forward  Start here….
  • 7. Q1.In case of negative work the angle between the force and displacement is (a) 00 ° (b) 450° (c) 900 ° (d ) 180°
  • 8. Watch the Video Again Attempt Again
  • 10. Q2. The work done on an object does not depend upon the (a) displacement (b) force applied (c) angle between force and displacement (d) initial velocity of the object
  • 12.
  • 13. Q3. A body of mass 15 kg undergoes downward displacement of 40 m under the effect of gravitational force. Calculate work done (g = 10 m/s2 Acceleration a= g = 10 m/s2 , mass m = 15 kg displacement s = 40 m a)-6000 J b) 6000 J c) 600 J d) 0 J
  • 14. Attempt Again Watch the Video Again
  • 16. Q4. A body of mass 120 g is taken vertically upwards to reach the height of 5m. Calculate work done (g = 10 m/s2) a) 6 J b) 600 J c) 0.6 J d) - 6 J
  • 19. Q5. Work done = Force x _______ a) distance b) acceleration c) velocity d) speed
  • 20. Next
  • 21. Attempt Again Watch the Video Again
  • 22. Q6. 1 joule = 1 _______ 1. N m2 2. kg/m2 3. N m 4. N2 m2
  • 25. Now Let Us Study about Energy  Let us read something
  • 26. Let Us Practice What we have learnt about Energy…
  • 27. Q7. A car is accelerated on a levelled road and attains a velocity 4 times of its initial velocity. In this process the potential energy of the car (a) does not change (b) becomes twice to that of initial (c) becomes 4 times that of initial (d) becomes 16 times that of initial
  • 30. Q8. Which one of the following is not the unit of energy? (a) joule (b) newton metre (c) kilowatt (d) kilowatt hour
  • 32.
  • 33. Q9. A body is falling from a height h. After it has fallen a height h/2 , it will possess (a) only potential energy (b) only kinetic energy (c) half potential and half kinetic energy (d) more kinetic and less potential energy
  • 35.
  • 36. Q10. When a body falls freely towards the earth, then its total energy (a) increases (b) decreases (c) remains constant (d) first increases and then decreases
  • 38.
  • 39. Q 11. Water stored in a dam possesses (a) no energy (b) electrical energy (c) kinetic energy (d) potential energy
  • 41.
  • 42. Q 12. When a spring is compressed its potential energy ……. a) Remains constant b) Reduces c) Increases d) Nothing can be said about it
  • 44.
  • 45. Q 13. A body of mass 10 kg performs motion along a circle of radius 5m with speed of 10 m/s. Work done during one revolution is ...... (A)2000 J (B)1000 J (C)500 J (D) zero
  • 47.
  • 49. Q14. 1 kWh= ........... J (A)36 X 106 (B)3.6 X 106 (C) 3.6 X 107 (D) 3.6 X l05
  • 50.
  • 51.
  • 52. Q 15.A boy of mass 40 kg climbs a staircase of 30 steps, each of 0.2m height, in 30 s. Calculate power (g = 9.8 m/s2) a. 8 W b. 80 W c. 18 W d. 9 W
  • 53.
  • 54.
  • 55. Q 16. Engine of a car of mass 1500 kg, keeps car moving with constant velocity 5m/s. If frictional force is 1000 N, power of engine is ............... (A)5 kW (B) 7.5 kW (C)15 kW (D) 75 kW
  • 56.
  • 57.
  • 58. Q 17.Height of water dam in hydroelectric power station is 20 m. How much water, in 1 second, should fall on turbine, so that 1MW power is generated ? (g = 10m/s2) (A)5000 kg (B)10,000 kg (C)500 kg (D)7,500 kg
  • 59.
  • 60.
  • 62. Q 18.The law of conservation of energy is a statement that A) energy must be conserved and you are breaking a law if you waste energy. B) the supply of energy is limited so we must conserve. C) the total amount of energy is constant. D) energy cannot be used faster than it is created.
  • 63.
  • 64.
  • 65. Q 19. The kinetic energy associated with the random motion of the constituent particles of a body, is known as a) Heat Energy b) Internal Energy c) Nuclear Energy d) None of the above
  • 66.
  • 67.
  • 68. Q 20.Mass and energy are mutually convertible according to the following relation a) M= EC2 b) E = mc2 c) E = 1/2mc2 d) None of the above