The Electric Potential Inside a 10-M Long Linear Particle Accelerator

The electric potential inside a 10-m long linear particle accelerator is given by V = 3,000 - 5x² volts,where x is the distance from the left plate along the accelerator tube,as shown in the figure.If a proton is released from rest at position x = 4.4 m,what is the impact speed of the proton when (and if) it collides with one of the plates?

A) never collides
B) 8.15 * 10² m/s
C) 1.36 * 10³ m/s
D) 2.78 * 10⁵ m/s