帮我解答PHYSICS

BooNBoX

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A wheel of radius r = 1 m rotates with an angular velocity w = 2.2 rad/s counter-clockwise, and an angular acceleration a = 1.6 rad/s clockwise. Determine the magnitude and direction of P at this instant.

P is located exactly above the wheel with tangent line slope m = 0. Direction y = vertical and x = horizontal.

jej1887

Assume the wheel is rolling without slipping. At any instant of time, the point on the wheel in contact with the ground is the instantaneous center of zero velocity. Thus the velocity of P is simply v = w(2r) = 2.2(2）＝4.4m/s to the left.