Question

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9-g6 The graph shows the torque on a rigid body as a function of time. The body is at rest at t = 2 s. Later, at t = 5 s, it is spinning at angular velocity 90 s-1 (a) What is the moment of inertia of the body? t(N m) 1 2 3 4 5 6 7

Question!

The graph shows the torque on a rigid body as a function of time. The body is at rest at t = 2s. Later, at t=5s, it is spinning at angular velocity 90 rad/s. What is the moment of inertia of the body?

Please give me full explanation Physic Masters! I really need them before Wednesday.

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Answer 1

​​​​​​please rate it up. This is the correct answer

As we know tau = I alpha From t = 2 to t = 5 tau = constant = 2 Nm Now at t_1 = 2 w_0 = 0 at t_2 = 5 w = 90 rad/s implies alpha = w - w_0/t_2 - t_1 = 90/3 = 30 rad/s^2 implies I = tau/alpha = 2/30 = 1/15 kg/m^2