Most Important Selected Qs for JEE AdvancedPhysicsRotational Motion
A horizontally uniform rod A B of mass m and length ₀ rotates freely about a stationary vertical axis OO' passing through the end A , which is located exactly midway between O and O ^ and OO ^ = . At what angular velocity (in units) of the rod is the horizontal component of the force acting on the lower end of the axis OO' equal to zero. ( g =10 m / s ^2, =5 ~m , ₀=3 ~m )
Correct answer
2
Step-by-step solution
About O N ^ + _ centrifugal + (- mg ₀ 2 )=0 About O ^ aligned & N + _ centrifiugal + (- mg ₀ 2 )=0 & _ centrifugal = ₀^ m ^2 2 ₀ xdx = 1 4 ~m ^2 _ (anticlockwise) & N ^ + 1 4 ~m ^2 ₀- mg ₀ 2 =0 & and N - 1 4 ~m ^2 ₀- mg ₀ 2 =0 & When N ^ =0, 1 4 ~m ^2 ₀- mg ₀ 2 =0 & = 2 ~g aligned