Question

1 Elastic collision A bumper car of mass m1 = 300kg is initially moving to the right at velocity V1, before = 8m/s and collides head-on with another bumper car of mass m2 = 200kg that is motionless, V2, before = 0. After the collision, the heavy bumper car is moving at a speed of v1,after = 1.6m/s. (a) (5 pts) Calculate the total kinetic energy before the collision (b) (5 pts) Calculate the kinetic energy of the heavy car after the collision (c) (5 pts) Find the kinetic energy of the lighter car after the collision. Hint: the total kinetic energy must be the same as in (a). (d) (10 pts) Find the speed of the lighter car after the collision.

Answer 1

Ame> C.009 lon=9am mass of wirst car (min=300 2.g. mase of and car (mal = 200 k.g. Nocty of heavy car (o,) before collirin= 8 mlres velocity of and can (lighten) c before coller velocity of heavy car after collision 2 = 1.6 mlrec velocity of lighter car after collision = ? According to principle of conservation of momentum? Total momentum before an Total momentum collision (P) = after collision (pt) - P = pl . . ete - eltel mu,+ maua = mult maua 300 (8) + 200 X (0) = 9 300 (itt 200 fugl) 2400 = 300 X[1:6) + 200 (0 - 2400-480 = 1920 = 966 mlrec. - Og = 200 200

Tan2 Total Hof, before the collision R atib bico01 bithre colline Rif. of car 1 t hit. of Cara RE. if A2 = 1/₂ m, u, 2+ / inguga Ug to mie E .. = VyX 300X (834 = 1x 300 x 64 = 9600 Total Rif before collision = aboo Joule To nie of heavy car after the collision → Т В. Сая л hts. с.21 лв. = y, m, 2, 3 Rifone = \_X 300 X (1.67* = 150 X 11698= 384 Joule The Rif of heavy case after the collision = 384 Joule 12.f. of the lighter canlalafter collision, + = Wymy lug = 14X200) x (4:6) = 100 X (9.64.9216 So 12.f. of lighter car after Casa Collision = 9216 Toule a speed of the lighter car - after the collson = ugl = 9.6 mis