Question

A system of three masses m1, m2 and ms are shown in the figure. The pulleys are smooth and massless; the strings are massless and inextensible. T, mg T. m, m. (1) Find the tensions in the strings. (ii) Find the acceleration of each mass.​

Answer 1

Answer:

Correct option is C)

Let tension produced string consisting of m

3

be T.Since m

3

has to be at rest,T should be equal to m

3

g.Now consider the lower pulley.Forces acting on this pulley are T

1

on one string and T

1

o the other string.Since tis pulley is at rest so

2T

1

=T and T

1

=

2

T

.

Now take acceleration of m

2

as a downwards and m

3

as a upwards.

Equation of motion of these two blocks are given,

2

T

−m

1

g=m

1

a⟶1

−

2

T

+m

2

g=m

2

a⟶2

divide eq.1 by eq.2 and rearrange the divided equations to get

m

4

3

=

m

1

1

+

m

1

2

, i.e. option c.