Physics 1 problem, did I do it right?

[James3shin]

So I'm helping my friend out with some physics 1, specifically momentum. The problem reads:

A radioactive nucleus, initially at rest, decays by emitting an electron and neutrino perpendicular to eachother. The linear momentum or the electron is 1.2x10-22 kgm/s and that of the neutrino is 6.4x10-23 kgm/s. Find the direction and magnitude of the linear momentum of the nucleus as it recoils.

I think I found the magnitube of the momentum by using the pythagorean theorem of the momentums and obtained:

1.36 x 10^-22 Kg m/s

For the direction portion, I tried taking the tangent of the two momentums and then taking the Tan inverse to get the degrees and I got:

1.875 degrees of deflection.

Correct or Incorrect?

 

[hypn0tik]

Originally posted by: James3shin
So I'm helping my friend out with some physics 1, specifically momentum. The problem reads:

A radioactive nucleus, initially at rest, decays by emitting an electron and neutrino perpendicular to eachother. The linear momentum or the electron is 1.2x10-22 kgm/s and that of the neutrino is 6.4x10-23 kgm/s. Find the direction and magnitude of the linear momentum of the nucleus as it recoils.

I think I found the magnitube of the momentum by using the pythagorean theorem of the momentums and obtained:

1.36 x 10^-22 Kg m/s

For the direction portion, I tried taking the tangent of the two momentums and then taking the Tan inverse to get the degrees and I got:

1.875 degrees of deflection.

Correct or Incorrect?

You have to be more specific. Set up a coordinate system. Let the electron be travelling in the positive y direction and the neutrino be traveling in the positive x direction. Which direction do you think the nucleus will be traveling in?

 

[James3shin]

Originally posted by: hypn0tik

Originally posted by: James3shin
So I'm helping my friend out with some physics 1, specifically momentum. The problem reads:

A radioactive nucleus, initially at rest, decays by emitting an electron and neutrino perpendicular to eachother. The linear momentum or the electron is 1.2x10-22 kgm/s and that of the neutrino is 6.4x10-23 kgm/s. Find the direction and magnitude of the linear momentum of the nucleus as it recoils.

I think I found the magnitube of the momentum by using the pythagorean theorem of the momentums and obtained:

1.36 x 10^-22 Kg m/s

For the direction portion, I tried taking the tangent of the two momentums and then taking the Tan inverse to get the degrees and I got:

1.875 degrees of deflection.

Correct or Incorrect?

You have to be more specific. Set up a coordinate system. Let the electron be travelling in the positive y direction and the neutrino be traveling in the positive x direction. Which direction do you think the nucleus will be traveling in?

I believe the nucleus will move in a line that would some where in the 3rd quadrant of that coordinate system (-x, -y)

 

[hypn0tik]

Originally posted by: James3shin

Originally posted by: hypn0tik

Originally posted by: James3shin
So I'm helping my friend out with some physics 1, specifically momentum. The problem reads:

A radioactive nucleus, initially at rest, decays by emitting an electron and neutrino perpendicular to eachother. The linear momentum or the electron is 1.2x10-22 kgm/s and that of the neutrino is 6.4x10-23 kgm/s. Find the direction and magnitude of the linear momentum of the nucleus as it recoils.

I think I found the magnitube of the momentum by using the pythagorean theorem of the momentums and obtained:

1.36 x 10^-22 Kg m/s

For the direction portion, I tried taking the tangent of the two momentums and then taking the Tan inverse to get the degrees and I got:

1.875 degrees of deflection.

Correct or Incorrect?

You have to be more specific. Set up a coordinate system. Let the electron be travelling in the positive y direction and the neutrino be traveling in the positive x direction. Which direction do you think the nucleus will be traveling in?

I believe the nucleus will move in a line that would some where in the 3rd quadrant of that coordinate system (-x, -y)

Bingo. See how easy the problem becomes once you set up a proper frame of reference?

 

[James3shin]

YAY! You rock Hypnotik!

 

[Mo0o]

momentum of electron <1.2e-22 , 0>
momentum of neutrno <0 , 6.4e-23>
momentum of nucleus <-1.2e-22 , -6.4e-23>

done and done

 

[James3shin]

Originally posted by: Mo0o
momentum of electron <1.2e-22 , 0>
momentum of neutrno <0 , 6.4e-23>
momentum of nucleus <-1.2e-22 , -6.4e-23>

done and done

I concur with that as well. But I don't think they wanted it in the format of a coordinate system.

 

[James3shin]

Is the 1.875 degrees of deflection correct?