Question

6. A 78 kg ice skater at rest throws a 6.0-kg bowling ball with a horizontal velocity of -3.0 msec What is the resulting velocity of the ice skater? 7. A 0.20-kg model railroad car moving with a horizontal velocity of 0.24 m/sec is struck from behind by a 0.42-kg car traveling at 0.45 m/sec. If the two cars stick together when they collide, what will their final velocity? 8. A 895-kg freight car coasts at 3.1 m/sec. A crane drops a 365-kg junk automobile into the freight car. What is the freight car's new speed? 9. An object has an angular momentum of 4.5 -. If the object's mass is 0.25 kg and it travel sec with a speed of 3.5 m/sec, what is its radius of motion? 10. A rock is twirled at the end of a string with a speed of 5.6 m/sec and an orbital radius of the string is suddenly let out so that the rock travels with a speed of 3.2 m/sec, wha radius?

Answer 1

Ison conservation of linear momentum Mitial momentum a Pinal momentum - motMV Given in= 60kg ball, va-3.0m/see, M2 Y skg ice skaker. » V - 6.0_43,0 79 V = 0.231 m/sec, velocity ofice » skaten. 7. of linoor. Agam using Conservation moment un according to quesfron, M&+muz (rem) g Geren, M = oning, v=0.4 m/sec, m=0.42kg, un 0.45 efsee, (on ton ) = (0.20 +0.42) kg 0.62 kg 2) 0.62 Valo. 20x0.24) + (6 428 0.45) - 0.620' = 0.237 Os 237 0.62 - n = 0.38 m/see This is the final velocity. >)

from Conservation of linear momentan MV = (M-mpre Given, M-895kg, freight Car 12 3.13/sec, (M-m - (895-365) kg 530kg, va? » 895x3.1 = 530 895 X 3.) - 70530 v - 5.235 m/se. freight Car on speed. This is the № 9. We have onegular momentun la rxp arome. Given a 4.5 kg. nussen. m-0.25kg, v=3.5 m/see, L 4.5 0:25 x 3.5 = n = 5.142 me. so a 5. 14m This is the rading of motion. we have Pernod of revolution T2 29 brunen - 2 Y, 2.34 ling o ) 2 = 344 3.2 This is the new se = 19.43n radius, 1 orstad