A proton is first accelerated from rest through a potential ...

[mia]

A proton is first accelerated from rest through a potential difference V and then enters a uniform 0.750-T magnetic field oriented perpendicular to its path. In this field, the proton follows a circular arc having a radius of curvature of 1.84 cm.
 
  What was the potential difference V? (mproton = 1.67  10-27 kg, e = 1.60  10-19 C)

Question 2

A rock is dropped from rest off of a high cliff on another planet, planet X. There is no atmosphere, and thus no air resistance, on planet X. At the end of 1 second, the rock is moving at a speed of 6 m/s.
 
  At the end of 2 seconds, it is moving at 12 m/s. How fast will the rock be moving at 4 seconds after being dropped?
  A) 20 m/s B) 40 m/s C) 24 m/s D) 18 m/s E) 36 m/s

[trampas]

Answer to Question 1

9.12 kV

Answer to Question 2

C

[mia]

Great answer, keep it coming

[atrochim]

Thanks for the timely response, appreciate it