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Please answer following questions asap for an upvote,
3. A wheel rotates from rest with constant 1 rad/s2 acceleration. After first 5s of rotation the wheel has rotated through 12.5 rad. What is the angular velocity of the wheel at the end of that 5s? How long will it take the wheel to rotate through next 50 rad? 4. A car 1 of mass M=100 kg collides with a car 2 (m=500 kg) moving with velocity v=3m/s in the same direction as car 1. During the collision they couple and move with speed V=5m/s. Calculate the velocity of the car 1 before the collision. What fraction of the initial kinetic energy was lost during the collision?