Question

How do I find net momentum? In the problem I am given that there is a 2300 kg truck traveling at 19 m/s in the -x direction, and a 1600 kg car traveling in the positive y direction. How do I find net momentum, and the direction of the net momentum?

Answer 1

@mathslover, could you help me with this?

Answer 2

What is the velocity of the 1600 kg car

Answer 3

Is it 19 m/s

Answer 4

I'm sorry, i meant to add it. It is 25 m/s

Answer 5

Ok

Answer 6

Now, I am going to use the law of vector addition

Answer 7

See,
Let the car having mass of 2300 kg = A
and that having 1600 kg = B

Answer 8

Now, total linear momentum,

P net vector = P (A) vector + P (B) vector

Answer 9

Now what is momentum ?

Answer 10

I mean what is momentum in terms of mass and velocity

Answer 11

@dave0616

Answer 12

momentum = p=m*v. The thing is though that I typed that into my online homework and it is not accepting it for some reason. I just want to make sure i am doing it right. I would assume that it is not looking for a signed value though, because it asks for the magnitude

Answer 13

I accept that

Answer 14

Now,

What is the momentum of A ?

It is,

P(A) vector = -2300 * 19 i cap

Answer 15

And

P (B) vector = 1600 * 25 j cap

Answer 16

Got it

Answer 17

so would you just add the value of those two together?

P(total)= (-2300*19)+(1600*25)=-3700?

Answer 18

No dude

Answer 19

You get total momentum as

P vector = P (A) vector + P (B) vector

P (vector) = -2300 * 10 i cap + 1600 * 25 j cap

Now, magnitude of momentum will be

\[P = \sqrt{(-2300 * 10)^2 + (1600*25)^2}\]

Answer 20

This will be the magnitude of total linear momentum

Answer 21

Got it ?

Answer 22

that makes complete sense, thank you very much mathslover

Answer 23

Your welcome

Answer 24

how would i go about finding the direction of the total momentum?

Answer 25

Allright

Lets make a nice diagram for that