If i=0.25 amp. In fig then value of R is:-

Options

A. 6
B. 10
C. 4
D. 5

Answer

D

Explanation

`a_(cm) = (m_(1)a_(1) + m_(2)a_(2))/(m_(1) + m_(2))`
(1) `a cos 60 = 4a`
`a_(M) = (5dsqrt3)/(8) m//s^(2)`
`N cos 30 = 4 ms_(M)`
`N(sqrt3)/(2) = 4(1) (5sqrt3)/(8)`
`rArr N = 5` Newton