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## Homework Statement

An electron (mass = 9.11 x 10

^{-31}kg) leaves one end of a tv picture tube with zero (0) initial speed and travels in a straight line to the accelerating grid, which is 1.80 cm away. It reaches the grid with a speed of 3.00 x 10

^{06}m/s; If the accelerating force is constant, compute:

a.) acceleration

b.) time to reach the grid

c.) net force in Newtons (gravitational force on the electron may be neglected)

**given:**

m = 9.11 x 10

^{-31}

v

_{o}= 0 m/s

v

_{F}= 3.00 x 10

^{06}

d = 1.80 cm = 0.018m

**In A:**

I've thought of two formulas. Both give different results. These are:

a = v/t

Since there is no TIME, I will have to solve for time using:

t = m(v - v

_{o}) / F

The other formula I have thought of is:

a = v

^{2}/ 2x (from v

^{2}= v

_{o}

^{2}+ 2ax)

**In B:**

It's either:

t = m(v - v

_{o}) / F

or

t = d/v

both giving different results again

**In C:**

It's obviously F = ma...

Please help me, I really don't know what formula to use.