- #1
quickclick330
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The total energy of a free electron moving through empty space is E=1.5mc^2, where m is the mass of the electron and c is the speed of light. What is this electron’s speed?
1. c (the speed of light)
2. 0.7453c
3. 0.8660c
4. 0.9428c
5. 0.9950c
6. 0.9999c
I thought since that Etotal = 1.5mc^2 then...
Etotal = KE = .5mv^2
1.5mc^2 = .5mv^2 and solve for v (masses would cancel which is what I was looking for)
What is wrong about this approach?
1. c (the speed of light)
2. 0.7453c
3. 0.8660c
4. 0.9428c
5. 0.9950c
6. 0.9999c
I thought since that Etotal = 1.5mc^2 then...
Etotal = KE = .5mv^2
1.5mc^2 = .5mv^2 and solve for v (masses would cancel which is what I was looking for)
What is wrong about this approach?