Saved Bookmarks
| 1. |
A block of mass M=4kg is moving with velocity V=6m/s toward a target block of mass=2kg, which is stationary (v=0). The object collide heat-on, and immediately after the collision, the speed of block m is 4 times the speed of block M. Q. Is the collision elastic? |
|
Answer» SOLUTION :A collision is ELASTIC if the TOTAL KINETIC energy is conserved. Since `K_("before")=(1)/(2)MV^(2)+(1)?(2)mv^(2)=(1)/(2)MV^(2)=(1)/(2)(4kg)(6m//s)^(2)=72J` and `K_(after)=(1)/(2)MV^(+2)+(1)/(2)mv^(+2)=(1)/(2)(4kg)(2m//s)^(2)+(1)/(2)(2kg)(8m//s)^(2)=72J` `K_("before")=K_("after")`, so the collision is elastic. |
|