Projectile Motion bombarding cancer tumors

[Grapz]

Homework Statement

You are asked to consult for the city's research hospital, where a group of doctors is investigating the bombardment of cancer tumors with high energy ions. The ions are fired directly toward the center of the tumor at speeds of 5.0 x 10 ^ 7 m/s. To cover the entire tumor area, the ions are deflected side-ways by passing them between two charged metal platest hat accelerate the ions perpendicular to the direction of their initial motion. The acceleration region is 5.0 cm long, and the ends of the acceleration plates are 1.5 m from the patient. What acceleration is required to move an ion 2.0 cm to one side?

Homework Equations

d = vt (1)
yf = yi + vi t + 1/2 a t^2 (2)

The Attempt at a Solution

I find the time it takes for it to hit the target
d / v = t
1.5 / 5.0 x 10 ^ 6 = 3.1 x 10 ^ - 7 s

Next i do use equation 2.

0.02 = 1/2 a ( 3.1 x 10 ^ -7) ^ 2
a = 4.4 ^ 10 - 11 m/s^2

The answer in the book says the answer is 6.52 x 10 ^ 12

Can someone help me out and straighten things out. The question i find is a bit ambigious, not exactly sure if i interpreted it right. thanks

 

[faoltaem]

maybe you could try working backwards to see what you've done wrong.
i think that you've used some values in the wrong places

 

[Grapz]

I have tried to work backwards.

When i do that, i get that the y value is 0.3 :/