A proton and an alpha particle are momentarily at rest at adistance r from each other. They then begin to move apart. Find thespeed of the proton by the time the distance between the proton andthe alpha particle doubles. Both particles are positively charged. The charge and the massof the proton are, respectively, e and m. The charge and the massof the alpha particle are, respectively, 2e =and 4m.
Find the speed of the proton Vf(p) by thetime the distance between the particles doubles.
Express your answer in terms of someor all of the quantities e, m, r, and epsilon 0.

The voltage applied across a given parallel-plate capacitor is doubled. how is the energy stored in the capacitor affected?

Two loudspeakers, 5.5 m apart and facing each other, play identical sounds of the same frequency. you stand halfway between them, where there is a maximum of sound intensity. moving from this point toward one of the speakers, you encounter a minimum of sound intensity when you have moved 0.33 m . assume the speed of sound is 340 m/s.part a) what is the frequency of the sound? part b) if the frequency is then increased while you remain 0.21 m from the center, what is the first frequency for which that location will be a maximum of sound intensity? express your answer to two significant figures and include the appropriate units.

Which statement is true if the refractive index of medium a is greater than that of medium b? a. total internal reflection is possible when light travels from air to medium b to medium a. b. total internal reflection is possible when light travels from medium a to medium b. c. total internal reflection is possible when light travels from medium b to medium a. d. total internal reflection is possible when light travels from air to medium a. e. total internal reflection is possible when light travels from air to medium b.