Home
Class 12
PHYSICS
In the figure shown all pulleys are idea...

In the figure shown all pulleys are ideal and small. The central pulleys is 2 m away from both ends. What is the length (in m) of the string ? The system is in equilibrium

A

`8/(sqrt(3))`

B

`4/(sqrt(4))[1+2/(sqrt(5))]`

C

`4/(sqrt(3))[1+2/(sqrt(3))]`

D

`2/(sqrt(3))+4`

Text Solution

Verified by Experts

The correct Answer is:
B

All pulley are smooth so tension in sring is same. At all points
For horizontal equilibrium at `P_(1)`
`T sin60^(@)`
For vertical equilibrium at `P_(3)`
`2T cos 60^(@) =20`
T=20 N
for vertical equilibrium at `P_(3)`
`2Txxcos theta=10`
`2xx20xxcos theta=10`
`rArr cos theta=1/4 rArr sin theta=(sqrt(15))/4`
`rArr ` length of string `=2 cosec 60^(@) +2 cosec theta`
`2xx2/(sqrt(3)) +2xx4/(sqrt(15)) =4/(sqrt(15))=4/(sqrt(3))(1+2/(sqrt(5)))`
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • TEST PAPERS

    BANSAL|Exercise PHYSICS PART (A)|32 Videos

  • TEST PAPERS

    BANSAL|Exercise PHYSICS PART (B)|3 Videos

  • TEST PAPERS

    BANSAL|Exercise PHYSICS PART- C|4 Videos

  • SEMICONDUCTORS

    BANSAL|Exercise CBSE Question|32 Videos

Similar Questions

Explore conceptually related problems

Three loads of mass m_(1),m_(2) and M are suspended on a string passed through two pulleys as shown in Fig. The pulleys are at the same distance from the points of suspension. Find the ratio of masses of the loads at which the system is in equilibrium. Can these conditions always be realized? The friction should be neglected.

Consider4 the situation shown in figure. Bothe the pulleys and the string are light and all the surfaces are friction less. a. Find the acceleration of the mass M. b. Find the tension in the string c. Calculate the force exerted by the clamp on the pulley A in the figure.

Knowledge Check

  • Two masses m and M are attached to the strings as shown in the figure. If the system is in equilibrium, then

    A
    `tantheta=1+(2M)/(m)`
    B
    `tantheta=1+(2m)/(M)`
    C
    `cottheta=1+(2M)/(m)`
    D
    `cottheta=1+(2m)/(M)`

  • If the string & all the pulleys are ideal, acceleration of mass m is :-

    A
    `g/2`
    B
    0
    C
    g
    D
    dependent on m

    • Similar Questions

    Explore conceptually related problems

    In the arrangement shown, the pulleys, string and the spring balance, all the ideal. If m_(1) gt m_(2) , then the reading of the spring balance is

    In the figure shown, the strings and pulleys are massless. The blocks are in equilibrium. If the force by the clamp on the pulley is sqrt(8/3) mg then (M)/(m) is equal to

    As shown in figure pulley is ideal and strings are massless.If mass m of hanging block is the minimum mass to set the equilibrium of system, then -

    In figure shown, pulleys are ideal m_(1)gt 2m_(2) . Initially the system is in equilibrium and string connecting m_(2) to rigid support below is cut. Find the initial acceleration of m_(2) ?

    Consider the situation shown in figure. Both the pulleys and the strings are light and all the surfaces are frictionless. Calculate (a) the acceleration of mass M, (b) tension in the string PQ and (c ) force exerted by the pulley P.

    In figure shown, pulley are ideal m_(1) gt 2m_(2) . Initially the system is in equilibrium and string connecting m_(2) to rigid support below is cut. Find the initial acceleration of m_(2) If m_(1)= 6 kg , m_(2) = 2.5 kg " and "g =10ms^(-2)

    Home
    Profile