Recent content by Barry Melby

Homework Statement Consider a searchlight on the ground that casts a spot on a cloud 1500 m overhead. If the searchlight is rotated rapidly−say, 40 ∘ in 1 μs−—how fast does the spot move in the Earth reference frame when the searchlight is directed vertically upward? I have solved this part...

The total energy would be zero i would suspect because they have no velocity. How does this relate to ##\gamma##?

it doesn't appear that the proton or antiproton are moving at all.

I don't really understand what you're saying. Do i have to do something with momentum?

No no, never mind. That wouldn't make sense. Where do i go?

Well i know that the mass of the proton and the antiproton are 1836.15 times the mass of the electron and positron. Would ##\gamma## = 1/(1-1836.15^2)?

i can't find ##\gamma##

how would i go about time dilation in this case?

Homework Statement [/B] Assume that 437 days is a reasonable limit for how long a human can endure constant-velocity space travel. Proxima Centauri, the star closest to our Sun, is 4.24 light years away from Earth. If you wanted to fly to Proxima Centauri within the 437-day limit in a rocket...

Homework Statement An electron e− and positron e+ moving at the same speed in the Earth reference frame collide head-on and produce a proton p and an antiproton p¯. The electron and positron have the same mass. The proton and antiproton also have the same mass. The mass of the proton is 1836.15...

i figured it out. thank you.

This is exactly what I'm doing: [(20 * 10^-6)(3 * 10^8)^2] / (2.5 * 10^3) = 720000000 which is incorrect.

c: 3.00 * 10^8 m/s m: 10 * 10^-5 kg

c: m/s m: kg

I realize that you should be able to take E / 2.5 * 10^3 J/m , but this is incorrect.