A 4.0kg object is mving at 5.0m/s SOUTH.It strikes a 3.0kg object that is moving WEST at 2.0m/s. The objects have a completely inelastic (stick together) collision. What is the kinetic energy lost in the collision?
2007-03-30 19:38:54 · 2 answers · asked by Anonymous in Science & Mathematics ➔ Physics
Ok, let's just find the velocity that both objects have, after the collision :
Let's work only with the magnitude of the linear momentum, so it will be easier for you :
Linear momemtum of the first object + linear momemtum of the negative object = linear momemtum of both objects, that will be traveling together because it's a complete inelastic collision :
4*5 + 3*2 = ( 4 +3)*v
20 + 6 = 7v
26/7 m/s = v
V =: velocity after the collision
Kinetic energy before the collision : 4*25/2 + 3*4/2 = 50 + 6 = 56 Joules
Kinetic energy after the collision : 7*(26/7)^2 / 2 = 49.29 Joules
Lost of energy = Initial energy - final energy : 56 - 49.29 = 6.71 Joules
Hope that helps
2007-03-31 04:25:26 · answer #1 · answered by anakin_louix 6 · 0⤊ 0⤋
http://img154.imageshack.us/img154/9421/rtangleinelasticcollisila9.png
2007-03-30 20:46:25 · answer #2 · answered by gp4rts 7 · 0⤊ 1⤋