Electric Potential- quick question about process

AI Thread Summary
The discussion revolves around calculating the distance of closest approach for an alpha particle colliding with a lead nucleus, given the alpha particle's kinetic energy of 10 MeV. A key point raised is the conversion of energy from MeV to joules, specifically why the kinetic energy is multiplied by 1.6e-19. This conversion is necessary to use the energy in the electric potential equation, V=kq/r. Participants emphasize the importance of understanding this conversion for solving similar physics problems. The conversation highlights the educational value of collaborative problem-solving in physics.
SuperCass
Messages
60
Reaction score
0
Electric Potential-- quick question about process

Homework Statement



An alpha particle with kinetic energy 10 MeV makes a head-on collision with a lead nucleus at rest. What is the distance of closest approach of the two particles? (Assume that the lead nucleus remains stationary and that it may be treated as a point charge. The atomic number of lead is 82. The alpha particle is a helium nucleus, with atomic number 2.)

Homework Equations



V=kq/r

The Attempt at a Solution



http://www.solvephysics.com/electricity_problem26.shtml
I tried going by this site to solve this. I would just like to know why in the Einitial equation they multiply the 10MeV by 1.6e-19. Why do they do that? I don't understand.

Thanks!
 
Physics news on Phys.org


SuperCass said:

Homework Statement



An alpha particle with kinetic energy 10 MeV makes a head-on collision with a lead nucleus at rest. What is the distance of closest approach of the two particles? (Assume that the lead nucleus remains stationary and that it may be treated as a point charge. The atomic number of lead is 82. The alpha particle is a helium nucleus, with atomic number 2.)

Homework Equations



V=kq/r

The Attempt at a Solution



http://www.solvephysics.com/electricity_problem26.shtml
I tried going by this site to solve this. I would just like to know why in the Einitial equation they multiply the 10MeV by 1.6e-19. Why do they do that? I don't understand.

Thanks!


http://en.wikipedia.org/wiki/Electronvolt
 


Thank you so much, I would have never gotten that on my own!
 


SuperCass said:
Thank you so much, I would have never gotten that on my own!

It should be in your textbook as well.
 
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Thread 'Variable mass system : water sprayed into a moving container'
Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
Back
Top