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If an object moves under
the effect of force then Work done in a unit of
mechanical work is done time is called power

WORK – W in unit of time POWER – P
(1 s)
textbooks nis edu kz

measured in
measured in is connected
with force and

joules (J) speed as
1 J = 1 N/m (SI) is defined as watts (W)

is defined as

Work = Force ∙ displacement
W = F ∙ d
Power = Force ∙ Velocity Power = work / time
P = F ∙ v P = W
t

equals zero is positive is negative
if force and displacement are if force and if force and
perpendicular to each other displacement are in displacement are in
F ⊥ s the same direction opposite directions

work done by gravity work done by the work done by the force
force equals zero child is positive of friction is negative

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