A disc has a moment of inertia of 0.3 kg m2 and an angular velocity of 4 rad/s. How much torque needed to increase the angular velocity to 6.5 rad/s in a time interval of 3 s.

Asailboat is traveling to the right when a gust of wind causes the boat to accelerate leftward at 2.5m/s2 for 4s. after the wind stops, the sailboat is traveling to the left with a velocity of 3.0m/s.assuming the acceleration from the wind is constant, what was the initial velocity of the sailboat before the gust of wind? answer using a coordinate system where rightward is positive.