| ppefmh | Ed | Garstin | | 51 | 4 | 6 | 204 | | -306 | Incorrect | 1 | Correct | 543
| | | | | | | | | |
| ppefmh | Ed | Garstin | 1/1 | 56 | 6 | 2 | 5 | | -112 | Incorrect | 2 | Incorrect | gf
| 54 | -18.666666666666668 | -18.67 | Incorrect | 4 | Incorrect | 45
|
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Initially the skateboard was stationary. This means that the momentum was zero. After the skateboarder jumps, their momentum is -20 kg m/s (i.e. acting backwards). This means that the momentum of the skateboard must be 20 kg m/s acting forwards. The backwards momentum after the jump is also zero.
-
Initially the skateboard was moving. This means that the momentum was more than zero. After the skateboarder jumps, their momentum is 20 kg m/s (i.e. acting forwards). This means that the momentum of the skateboard must be -20 kg m/s acting backwards. The backwards momentum after the jump is also greater than zero.
-
Initially the skateboard was moving. This means that the momentum was less than zero. After the skateboarder jumps, their momentum is 20 kg m/s (i.e. acting forwards). This means that the momentum of the skateboard must be -20 kg m/s acting backwards. The backwards momentum after the jump is also less than zero.
| 100% |
| ppefmh | Ed | Garstin | 1/1 | 54 | 1 | 8 | 54 | | -432 | Incorrect | 1 | Correct | gfg
| 45 | 432 | 432 | Incorrect | 2 | Correct | fdf
|
-
Initially the skateboard was stationary. This means that the momentum was zero. After the skateboarder jumps, their momentum is -20 kg m/s (i.e. acting backwards). This means that the momentum of the skateboard must be 20 kg m/s acting forwards. The backwards momentum after the jump is also zero.
-
Initially the skateboard was moving. This means that the momentum was more than zero. After the skateboarder jumps, their momentum is 20 kg m/s (i.e. acting forwards). This means that the momentum of the skateboard must be -20 kg m/s acting backwards. The backwards momentum after the jump is also greater than zero.
-
Initially the skateboard was moving. This means that the momentum was less than zero. After the skateboarder jumps, their momentum is 20 kg m/s (i.e. acting forwards). This means that the momentum of the skateboard must be -20 kg m/s acting backwards. The backwards momentum after the jump is also less than zero.
| 100% |
| ppefmh | Ed | Garstin | 1/1 | 59 | 2 | 2 | 54 | | -118 | Incorrect | 1 | Correct | 543
| 543 | 59 | 59 | Incorrect | 2 | Correct | 543
|
-
Initially the skateboard was stationary. This means that the momentum was zero. After the skateboarder jumps, their momentum is -20 kg m/s (i.e. acting backwards). This means that the momentum of the skateboard must be 20 kg m/s acting forwards. The backwards momentum after the jump is also zero.
-
Initially the skateboard was moving. This means that the momentum was more than zero. After the skateboarder jumps, their momentum is 20 kg m/s (i.e. acting forwards). This means that the momentum of the skateboard must be -20 kg m/s acting backwards. The backwards momentum after the jump is also greater than zero.
-
Initially the skateboard was moving. This means that the momentum was less than zero. After the skateboarder jumps, their momentum is 20 kg m/s (i.e. acting forwards). This means that the momentum of the skateboard must be -20 kg m/s acting backwards. The backwards momentum after the jump is also less than zero.
| 100% |
