Auctions of Motion: Rectangular Coordinates At the instant shown the 100-lb bloc
ID: 1718155 • Letter: A
Question
Auctions of Motion: Rectangular Coordinates At the instant shown the 100-lb block A is moving down the plane at 5 ft/s while being attached to the 50-lb block B. If the coefficient of kinetic friction between the block and the incline is mu_k = 0.2, determine the acceleration at A and the distance A slides before it stops. Neglect the mass at the pulleys and cables. 13-29. The force exerted by the motor on the cable is shown in the graph. Determine the velocity of the 200-lb :rate when t = 2.5 s.Explanation / Answer
From Newtons 2nd law,
mB x g - T = mB x a
T - mA x g x sin = mA x a
= Sin-1(3/5) = 37°
Substituting for T,
mB x g - mA x g x sin - mA x aA= mB x a
a = mB g - mA x g x sin / mA+mB = 222.4 x 9.81 - 444.8 x 9.81 x Sin 37° / (222.4+444.8) = -444.25/667.2 = -0.67 m/s2 = 0.67 m/s2 deceleration
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.