# Momentum and waves

A 3kg particle has a velocity of (3i-4j) m/s. Find the magnitude of its momentum?

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Answers:

a) 9kg m/s

b) -12 kg m/s

c) 15 kg m/s

d) 3 kg m/s

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A sinusoidal wave is described by y=(0.30m)sin(0.20x-40t). Determine the wave speed.

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Answers:

a) 100 m/s

b) 133 m/s

c) 150 m/s

d) 200 m/s

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OTA: Please take this problem only if you can show step by step problem solving techniques and equations used. Thank you.

a) 100 m/s

b)

https://brainmass.com/physics/wavefunction/momentum-and-waves-23282

#### Solution Preview

Hello and thank you for posting your problem to Brainmass.

Here is my solution:

The momentum vector is the velocity vector multiplied by the mass of the particle:

P=mV

V=3i-4j

m=3

P=3(3i-4j)=9i-12j

To find the total magnitude of the momentum, one must find the magnitude of the vector:

|P|=sqrt(Px^2+Py^2)

Where Px is ...

#### Solution Summary

The solution provides answers to the two questions. It shows how to find the magnitude of the momentum vector and how the Dlambert solution is applied to the sine wave.