CHAPTER-5
What are you
doing my child ?
Don’t you see I am
doing my work.
Ha.. Ha…
Are you doing
work ?
Why are you laughing
..i am putting lot of force
to move you
I didn’t move even a
single step. Then how
can you say that you
are doing work?
What is he
saying ?
Pic 1 Pic 2
Pic
3
❖ What are the pictures did you see ?
❖ Is there any force acting on these three situations?
❖ Can you say the source of applied force in “an
apple falling from the tree”?
❖ What about the source of applied force in second
picture?
❖ Who applied force in third picture?
❖ Is there any displacement takes place in above
pictures?
❖ In which cases displacement is not happened?
❖ Which bodies undergo displacement in first and
second picture ?
❖ Is the force and displacement in same direction?
❖ Force are applied on bodies in all the above
situations but displacement does not takes place
isn’t it?
❖ Can we say that work is done in all the above
these pictures?
❖ What are the situations in which work is done
and not done?
❖ Can you define work?
❖ How can we relate work displacement and force?
❖ What do you observed in case 1?
❖ Is there any work done here?
❖ What is the reason?
❖ What do you observed in case 2?
❖ In which direction force is applied?
❖ In which direction displacement is takes place?
❖ Is there any work done here?
❖ What are the factors influence the work done?
❖ How can we relate work, force, displacement?
❖ What is the unit of force and displacement?
❖ What is the unit of work?
❖ A force of 10N is applied continuously on a body.
If the body undergoes a displacement of 2m, find
out the magnitude of work done?
� F = 10N
� S = 2 m
� W = F * S
� = 10*2
� = 20 Nm
� = 20 J
❖ WORK IS SAID TO BE DONE
ONLY WHEN A BODY
UNDERGOS DISPLACEMENT
IN THE DIRECTION OF
APPLIED FORCE
WORK
❑ IF A FORCE OF F NEWTON IS
APPLIED COTINUOUSLY ON A
BODY AND THE BODY UNDERGOES
A DISPLACEMENT OF S METRE IN
THE DIRECTION OF THE FORCE,
THEN THE WORK DONE BY THE
APPLIED FORCE IS,
W= F.S
CHOOSE THE DISPLACEMENT
TAKES PLACE IN THE DIRECTION
OF FORCE AND NO
DISPLACEMENT FOR THE BODY IN
THE DIRECTION OF FORCE
APPLIED.
A car is pushed
by sitting inside
the car
A trolley is being pulled
Climbing
ladder with
load on head
FOLLOW UP
� Define work done?
�A force of 40 N applied on body and
its displacement in the direction of
force is 10m. Find work done?
�What is the unit of work?
� F=40N
� S=10m
� W=F*S
� =40*10
� = 400J
CREATE A CARTOON RELATING
THE WORK DONE.

Work

  • 1.
  • 2.
    What are you doingmy child ? Don’t you see I am doing my work.
  • 3.
    Ha.. Ha… Are youdoing work ? Why are you laughing ..i am putting lot of force to move you
  • 4.
    I didn’t moveeven a single step. Then how can you say that you are doing work? What is he saying ?
  • 5.
  • 6.
  • 8.
    ❖ What arethe pictures did you see ? ❖ Is there any force acting on these three situations? ❖ Can you say the source of applied force in “an apple falling from the tree”? ❖ What about the source of applied force in second picture? ❖ Who applied force in third picture? ❖ Is there any displacement takes place in above pictures?
  • 9.
    ❖ In whichcases displacement is not happened? ❖ Which bodies undergo displacement in first and second picture ? ❖ Is the force and displacement in same direction? ❖ Force are applied on bodies in all the above situations but displacement does not takes place isn’t it? ❖ Can we say that work is done in all the above these pictures?
  • 10.
    ❖ What arethe situations in which work is done and not done? ❖ Can you define work? ❖ How can we relate work displacement and force?
  • 13.
    ❖ What doyou observed in case 1? ❖ Is there any work done here? ❖ What is the reason? ❖ What do you observed in case 2? ❖ In which direction force is applied? ❖ In which direction displacement is takes place? ❖ Is there any work done here? ❖ What are the factors influence the work done? ❖ How can we relate work, force, displacement?
  • 14.
    ❖ What isthe unit of force and displacement? ❖ What is the unit of work? ❖ A force of 10N is applied continuously on a body. If the body undergoes a displacement of 2m, find out the magnitude of work done?
  • 15.
    � F =10N � S = 2 m � W = F * S � = 10*2 � = 20 Nm � = 20 J
  • 17.
    ❖ WORK ISSAID TO BE DONE ONLY WHEN A BODY UNDERGOS DISPLACEMENT IN THE DIRECTION OF APPLIED FORCE WORK
  • 18.
    ❑ IF AFORCE OF F NEWTON IS APPLIED COTINUOUSLY ON A BODY AND THE BODY UNDERGOES A DISPLACEMENT OF S METRE IN THE DIRECTION OF THE FORCE, THEN THE WORK DONE BY THE APPLIED FORCE IS, W= F.S
  • 19.
    CHOOSE THE DISPLACEMENT TAKESPLACE IN THE DIRECTION OF FORCE AND NO DISPLACEMENT FOR THE BODY IN THE DIRECTION OF FORCE APPLIED.
  • 20.
    A car ispushed by sitting inside the car A trolley is being pulled Climbing ladder with load on head
  • 21.
    FOLLOW UP � Definework done? �A force of 40 N applied on body and its displacement in the direction of force is 10m. Find work done? �What is the unit of work?
  • 22.
    � F=40N � S=10m �W=F*S � =40*10 � = 400J
  • 23.
    CREATE A CARTOONRELATING THE WORK DONE.