- #1
am13
- 7
- 0
Homework Statement
A proton with mass 1.67 x 10^-27 kg is propelled at an initial speed of 3.00x10^5 m/s directly toward a uranium nucleus 5.00 away. The proton is repelled by the uranium nucleus with a force of magnitude F=α/x^2, where x is the separation between the two objects and α = 2.12 x 10^-26 N*m^2. Assume that the uranium nucleus remains at rest.
A)What is the speed of the proton when it is from the uranium nucleus?
B)As the proton approaches the uranium nucleus, the repulsive force slows down the proton until it comes momentarily to rest, after which the proton moves away from the uranium nucleus. How close to the uranium nucleus does the proton get?
Homework Equations
v22=vv[2/SUB]+2ad
F=α/x^2 (given)
Fd=KE2-KE1
KE = .5mv2
The Attempt at a Solution
For a), I got that the distance equaled 5-8*10^-10 = 5 m, and I tried using that distance times the force (found with the given equation), to find the work and I set that equal to the the change in Kinetic energy, and tried to find the second velocity. But this did not get me the right answer. For b) I tried the sae approach, but plugged in the known velocities, canceling out KE2 because v = 0 there, and still didn't get the right answer. What am I doing wrong? Thanks.