Question

A particle of mass m connected with the help of string of length lis released from rest, when string is horizontal. Tension in string when particle is at lowest point, is​

Answer 1

(A) as the collision is perfectly inelastic, velocity after collision is v

0

sin37

o

=

5

3

v

0

towards right till string becomes shut

∴R=

a

⊥

v

2

=

gsin37

o

v

0

2

=

3g

5v

0

2

(B) from figure, cosθ=

2

1

⇒θ=60

o

after string becomes tart particle motion will seize along the string due to impulse. Just after impulse velocity of particle is

5

3

v

0

cosθ=

10

3

v

0

perpendicular to the string from conservation of mechanical energy,

2

1

m(

10

3

v

0

)

2

=

2

1

m(

2g

)

2

+2mg(1+cos60)

simplifying, v

0

=

3

20

2g

m/s

(C) W

G

=−2mg(1+cos60)=−3mg

∴−W

G

=3mg

(D) At highest point velocity will be perpendicular to gravitational force

∴P=

F

.

V

=0