Question

5. For this series of 4 questions, a rider rides in a car that is connected to a 4-m rod, and rotates about the z axis. The rod of negligible mass is subjected to a constant couple moment of M, and the engine of the car supplies a traction force of F. Neglect the size of the car. You will be asked to solve for different things. Please pay attention: the numbers may change from problem to problem since they are randomized. 4) If the total mass of the car and the rider is 180 kg, the rod is subjected to a constant couple moment of M = 640 N·m, and the engine of the car supplies a traction force of F=15.t N to the wheels, where tis in seconds, determine how much time it will take before the speed of the car reaches a speed of 4.9 m/s if the car starts from rest. Your answer must include 2 places after the decimal point and the proper unit. z -4 m M F

Answer 1

M+= 180kg F=15+N , V =4.9mis M = 640N.m., visomis net moment, Mr = M+ (F)4 Mn = 6401 1584t Mn = 64 0 + 60t moment of inertia about z-axis I=M(4)2 = 180x16=288 Okgm? moment = 12 where &- angular acceleration. 640 +60t = Ia

x = dw dt when o=4.9mis, W=u r W = 4.9 -1.225 919 disa

640 +60t - Idw dt 40 +60 t)dt 1.225 Ildw S640 [6404 504) Sow 640t + 60 t²nt IX1-225 640t + 30 t² = 288 0X1-225 30+2 +6407 = 3528 30ť? + 6401 - 3528 =0 t=4.545