Page 15 - TYPES OF FORCES (FRICTIONAL , GRAVITATIONAL, MAGNETIC AND BOUYANT FORCES)

7. BUOYANT FORCE:
7 . B U O Y A N T FO R C E :

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f
f
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n

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Buo
n
er
t
a
y
w

a
t
e
th
rd

p

up
• •Buoyant force is the upward push of water on a
w
a
e
us
is
a

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t.
g
b

o

j
ec
l
tin
o
a
f
floating object.
rc

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a
e

a

s
• •It is defined as the upward force exerted by a
e
a
w
up
f

th
rd

I
b

t
in

d
is
ef
y
ed
exerted
f l uid o n a n o b j ec t w h en it is p l a c ed in t h e f l uid .
fluid on an object when it is placed in the fluid.
When we push a mug or piece of wood in water,
Wh en w e p us h a m ug o r p iec e o f w o o d in w a t er,
we can feel an upward thrust.
w e c a n f eel a n up w a rd t h rus t.
t
l
ke
p
s
ty
o
a
t
a
e
b
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t
em

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p

e:
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f
I
o
F
• •For example: If we take an empty plastic bottle
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p
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exa
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ta
e
o
p
.

l
w
a
c
a
s
its
e

n
n
w
e
and close its mouth with an airtight cap. Then we
a

T
c
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e
d
ith

o
m
a
t
n

uth
irtigh
w il l try to p us h t h is b o t tl e in a b uc ke t f il l ed w ith
will try to push this bottle in a bucket filled with
th
o
a
a
th
s
water. We will observe that a force pushes the
e

t
b
w
e

il
rc
l
h
us
e
w
a
We
p
s

e
ter.
erv

o
f
b o ttl e in th e b uc ket up w a rd s . T h is is d ue t o
bottle in the bucket upwards. This is due to
buoyant force.
b uo y a n t f o rc e