Recent content by byerly100

I was wondering exactly where you started in the file. It looks like you started around https://www.physicsforums.com/showpost.php?p=1129304&postcount=6.

l^2cos^2(theta) - 2beta*c*tau'*l*cos(theta)gamma + [l^2{1-cos^2(theta)}]gamma= c^2tau'^2 l^2cos^2(theta) - 2beta*c*tau'*l*cos(theta)gamma + [{l^2-l^2cos^2(theta)}]gamma= c^2tau'^2 What do I need to do to get the below? At some point, I need to combine the cos^2 terms. "quadratic 0 =...

[(l*cos(theta)/gamma - v*tau')^2 + (l*sin(theta))^2 = d^2 = (c*tau')^2 [(l*cos(theta)/gamma - v*tau')^2 + (l*sin(theta))^2]^(1/2)/c=tau' "most easily handled in terms of the combination c*tau'/gamma"

Could you give some more detail on "length contraction in the x direction to figure out the coordinates of P in S' when the pulse is" emitted? l= l_p/gamma Also, (c*tau')^2=(v*tau')^2+(x)^2 ?...

I got the answer.

A flash of light is emitted at point O and is later reabsorbed at point P. In frame S, the line OP has a length l and makes an angle theta with the x axis. In a frame S' moving relative to S with a constant velocity v along the x axis: How much time tau' elapses between emission and absorption...

ux'=(ux-v)/(1-vux/c^2) I got 0.185c. I used 1.8x10^8 m/sec for one v and 2.12x10^8 m/sec for another v.

v= c^2p/E ux=ux'+v/(1+vux'/c^2) I got something for part c but it was off (wrong).

A particle of rest mass m. and kinetic energy 2m.c^2 strikes and sticks to a stationary particle of rest mass 2m.. Find the rest mass M. of the composite particle. (.=zero subscript) The answer is (17)^1/2(m.)

4 x 10^9 eV / 931.49 x 10^6 eV = 4.3 amu (should there not be a /c^2 in the conversion information?) I'm trying c now. v/c = cp/E v=c^2p/E v. = c^2(3 GeV/c) / 4 GeV = 2.25x10^8 m/sec v=2.12x10^8 m/sec I got u= 2.86x10^8 m/sec...

16Gev^2=E.^2 4 GeV= E. 931.49 MeV/c^2 = 1 amu

Yes, I was using the dot for 0 subscript. E^2-(16 GeV^2)=16 GeV^2 E= 5.66 GeV I could also use help on the rest of the problem, b and c.

I probably didn't account for both frames. How did you use the 4 GeV/c?

c) What is the relative velocity of the two reference frames?

Are you saying to take the derivative of u'?