The 130-lb boy has taken a running jump from the upper surface and lands on his 19-lb skateboard with a velocity of 13 ft/sec in the plane of the figure as shown. If his impact with the skateboard has a time duration of 0.05 sec, determine the final speed v along the horizontal surface and the total normal force N exerted by the surface on the skateboard wheels during the impact. 270 13 ft/sec Answers: V = i ft/sec N = i Ib

The 64.4-lb slider moves in the vertical plane on a smooth rail. The spring with k = 800 lb/ft is unstretched with the slider at point B. If the slider is released from rest at point A, what is the speed at point C? The slider can be approximated as a particle. 인 it woll 3 ft C abert --www- A B 3 ft

The 52 kg block is hoisted up the incline using the cable and motor arrangement shown. (Figure 1) Figure 2 m/s Part A The coefficient of kinetic friction between the block and the surface is = 0.4. If the block is initially moving up the plane at v0 = 2 m/s, and at this instant (t = 0) the motor develops a tension in the cord of T = (300+120√t) N, where t is in seconds, determine the velocity of the block when t = 4 s. Express your answer to three significant figures and include the appropriate units. v2 = Submit Value Provide Feedback A Request Answer → Ò Units ? Next >

Q15. As shown in the image below, the 17-kg crate is being hoisted by the motor. If at this instant shown the velocity of point P on the cable is vp = 2.6 m/s and the speed is increasing at 1.3 m/s², what is the power input supplied to the motor if its efficiency is e = 0.63? Please pay attention: the numbers may change since they are randomized. Your answer must include 1 place after the decimal point, and proper Sl unit. Take g = 9.81 m/s². Vp Your Answer: P Answer D A units

The 214000-lb space-shuttle orbiter touches down at about 222 mi/hr. At 182 mi/hr its drag parachute deploys. At 40 mi/hr, the chute is jettisoned from the orbiter. If the deceleration in feet per second squared during the time that the chute is deployed is -0.000200v2 (speed v in feet per second), determine the corresponding distance s traveled by the orbiter. Assume no braking from its wheel brakes. Answer: s = i ft