Average Momentum: 1552.795 kg m/s

[mailmas]

Homework Statement

m = 50kg
Distance covered = 100m
T = 3.22
Solve for average momentum.

Homework Equations

X = 1/2 at^2
p = mass*acc*change time

The Attempt at a Solution

100 = 1/2 a (3.22)^2
a = 200/10.3684 = 19.28937m/s^2
f = 50 * 19.28937 = 964.4689
change momentum = 964.4689 * 3.22 = 3105.59 kg m/s

The answer is half of this, why exactly is it half?

 

[TSny]

You should state the problem word for word as given. I suspect that you did not give all the information specified in the problem.

Note that they ask for average momentum, not change in momentum.

 

[mailmas]

You should state the problem word for word as given. I suspect that you did not give all the information specified in the problem.

Note that they ask for average momentum, not change in momentum.

Sorry, all the information is there though. The only problem I have is understanding how to solve for the average momentum. Would it be change in momentum/ #momentum's considered. Maybe to clarify I'm considering the object is moving in a straight line and that the acceleration is constant.

 

[TSny]

Sorry, all the information is there though.

Note that an object could cover a distance of 100 m in 3.22 s without any acceleration.

EDIT: Maybe you have included all the necessary information to answer the question. But there is not enough information to determine the acceleration.

Since momentum is defined as p = mv, how would average momentum be related to average velocity?

 

[mailmas]

Note that an object could cover a distance of 100 m in 3.22 s without any acceleration.

EDIT: Maybe you have included all the necessary information to answer the question. But there is not enough information to determine the acceleration.

Since momentum is defined as p = mv, how would average momentum be related to average velocity?

Average momentum = 50* (vf- vi)/change time
=15.52*vf

 

[mailmas]

Note that an object could cover a distance of 100 m in 3.22 s without any acceleration.

EDIT: Maybe you have included all the necessary information to answer the question. But there is not enough information to determine the acceleration.

Since momentum is defined as p = mv, how would average momentum be related to average velocity?

Never mind I got it thanks! Forgot change in velocity = change position/ change time and then I just multiplied by mass.