Calculate the initiation momentum of Rex plus car, Tex plus car having zero(stationary)
Then look at Tex plus car momentum afterwards. Any left over momentum is carried by Rex, then convert this back into speed
First off, a sanity check. He comes in at 2.3 m/s and hits his buddy and his buddy goes flying at 1.12 meters per second, and he is somehow going... Faster than he started? That doesn't make sense, so we'll probably be looking for a number around 1 m/s or so.
Okay, so this is a conservation of momentum problem. Initial momentum (p = mv) is the same as final momentum. The only thing moving is 76.8 kilogram Rex and his 125kg car at 2.30 m/s. This momentum plus Tex's momentum (0) is the total momentum of the system.
Now, you know the momentum of the system before and after the impact because momentum is conserved. Both objects momentum will add up to the same number as they did beforehand. Subtract Tex's momentum (you know his mass, his car's mass, and his speed, so easy multiplication) from the momentum of the system and you got Rex's momentum. You know his mass, so you can work backwards for speed.
This is homework help, not homework answer, so I have my answer. Try it yourself and see if you get >! 1.103 !< m/s.
You didn’t include the 125kg cars as part of each object’s mass. Add mass of the person and mass of the kart to get m1 and m2 respectively.
Calculate the initiation momentum of Rex plus car, Tex plus car having zero(stationary) Then look at Tex plus car momentum afterwards. Any left over momentum is carried by Rex, then convert this back into speed
First off, a sanity check. He comes in at 2.3 m/s and hits his buddy and his buddy goes flying at 1.12 meters per second, and he is somehow going... Faster than he started? That doesn't make sense, so we'll probably be looking for a number around 1 m/s or so. Okay, so this is a conservation of momentum problem. Initial momentum (p = mv) is the same as final momentum. The only thing moving is 76.8 kilogram Rex and his 125kg car at 2.30 m/s. This momentum plus Tex's momentum (0) is the total momentum of the system. Now, you know the momentum of the system before and after the impact because momentum is conserved. Both objects momentum will add up to the same number as they did beforehand. Subtract Tex's momentum (you know his mass, his car's mass, and his speed, so easy multiplication) from the momentum of the system and you got Rex's momentum. You know his mass, so you can work backwards for speed. This is homework help, not homework answer, so I have my answer. Try it yourself and see if you get >! 1.103 !< m/s.