Concept explainers
14.19 and 14.20 Cruiser A was traveling east at 60 mi/h on a police emergency call when it was hit at an intersection by car B, which was traveling south at high speed. After sliding together on the wet pavement, the two cars hit cruiser C, which was traveling north at 45 mi/h and was 63 ft from the intersection at the time of the first collision. Stuck together, the three cars hit a wall and came to a stop at D. Knowing that car B weighs 3600 lb and that each of the cruisers weighs 3000 lb, solve the problems below neglecting the forces exerted on the cars by the wet pavement and treating the cars as point masses.
14.20 Knowing that the speed of car B was 75 mi/h and that the time elapsed from the first collision to the stop at D was 1.5 s, determine the coordinates of D.
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Vector Mechanics for Engineers: Statics and Dynamics
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- Car A with a constant velocity of 6.1 ft/s is heading east and in an instant that Car B with an initial velocity of 2.75 ft/s is traveling southwest at a constant rate of 0.05 ft/s2. The bearing of Car B from Car A is 30 deg north of east and the distance between them is 4800 ft. (a) Prove whether or not both Cars will collide in 5 mins. (b) What is the distance between the two cars in 10 mins? Show free body diagram.arrow_forward11.20 A spring AB is attached to a support at A and to a collar. The unstretched length of the spring is 1. Knowing that the collar is released from rest at x = xo and has an acceleration defined by the relation a = -100(x- Ix/yR +x²), determine the velocity of the collar as it passes through point C.arrow_forwardA Fig. P11.140 150 m B -100 m Carrow_forward
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- Two cars A and B are approaching each other in adjacent lanes of a highway. In t = 0, A and B are 1 km apart, their speeds are vA= 112.5 km/h and vB= 75.0 km/h, and they meet at points P and Q, respectively. Knowing that A passes through point Q 40 seconds after B, and that B passes through point P 42 s after A, determine the speed of B (in km/h) when the vehicles pass each other. . A P 1 km VB Barrow_forwardPROBLEM 11.140 В A motorist starts from rest at Point A on a circular entrance ramp when t = 0, increases the speed of her automobile at a constant rate and enters the highway at Point continues to increase at the same rate until it reaches 100 km/h at 100 m Knowing that her speed 150 m Point C, determine (a) the speed at Point B, (b) the magnitude of the total acceleration when t = 20 s.arrow_forward13.4 A disk is projectedwith an initial velocity of 10m/s up an incline as shown. If pg=0.2 between the disk and the incline determine (a) the maximum distance L which the disk will travel up the incline, and (b) the speed of the disk as it slide back through the original providence.arrow_forward
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