Question

4.
In the set-up shown, a 200 N block is supported
in equilibrium with the help of strings and a spring,
all knotted at ponit O. Extension in the spring is
4 cm. Force constant of the spring is closest to
lg = 10 m/s)
37°
530
V00000000
(1) 30 N/m
(3) 3000 N/m
200 N
(2) 2500 N/m
(4) 4000 N/m​

Answer 1

Answer:

The answer will be 3000 N/m

Explanation:

According to the diagram we can see that the mass of block is 200 N

let the tension is string is t1 and tension in spring is t2

For this problem we will use lami's theorem

Therefore according to the lami's theorem,

t1/sin(90+37) = t1/sin(90+53) = 200/sin90

Therefore t2/sin143 = 200/sin90

t2/sin(180-37) =200   [ as sin 37 = 3/5]

therefore 5t2/3 = 200

                 => t2 = 120 N

Therefore the foce in the string is 120 N

let the force constant be c

Therefore f = cx

              => 120 = k x 4 x 10^(-2)

              => c = 3000 N/m