contain description of work, energy and power in terms of physics. Useful for plus one science classes

1. WORK, ENERGY
AND POWER
KRISHNA PRIYA T V
PHYSICAL SCIENCE
Roll.No:32
Reg.No:DD16EDPS02

2. WORK
Work done means a body displaced along
the same direction of applied force.
Simply work is the product of force and
displacement.
W=Fd
Unit = joule(J)
Dimension= [ML2T-2]

3. W= (Fcosθ)d= F.d

4. TYPES OF WORK
Positive work
Zero work
Negative work

6. Work Done by a Constant Force
y

7. Work Done by a Non-Constant Force

8. Work Done by a Continuously Varying
Force

9. Force
The average force times
the distance gives the
work. This is the same as
the area under the curve.
Distance
Work done by a variable force
The area under a force-distance
curve is the work, W.

10. Conservative & Non- conservative force
Conservative force depend initial and final point of
motion. ie, does not depend travelling path.
Eg: Gravitational force
Non- Conservative forces are path depending force.
Eg: Frictional force

11. Work = change in KE
This is called:
the Work-Energy Theorem
W= ΔK

12. Mechanical Energy
Kinetic Energy Potential Energy

13. Kinetic Energy
K = ½ m V2
Energy possessed by virtue of its motion.

14. Potential Energy
mg
h
PEmghW
hxmgFxFW



10cos,0
;cos



It is the energy possessed by
virtue of its configuration or
position.

15. Work done by a spring
Relaxed
Position
F=0
F
x
I compress
the spring
(I do + work;
spring does
-work)
Work done by spring = - change in ½kx2

16. Force
Distance X
F-x Graph
Area of triangle=F x= ½kx2
Area under F-x graph of a
spring= Its potential energy

17. h
x
(h-x)
Principle of Conservation of Energy
A
B
C
At point A
V=mgh& K= 0& TE= mgh
At point B
V=mg(h-x)& K= mgx& TE=mgh
At point C
V=0& K=mgh& TE= mgh

18. POWER
Rate of work with respect to time.
P= W/t= F.V
SI unit= watt (W)
1 W = 1 J/S
Dimension= [ML2T-3]

19. 1hp = 746W
Horse Power

20. Thank you…