Question

A uniform electric field exists in a region between two oppositely charged plates. An electron is released from rest at the surface of the negatively charged plate and strikes the surface of the opposite plate, 2.0 cm away, in a time 1.5 x 10-8 s. The speed of the electron in millions m/sec as it strikes the second plate is: A. 13.3 B. 133 C. 2.67 D. 26.7 E. 534

Answer 1

A. 13.3

Step-by-step explanation:

First, we find the velocity of the electron in meters/sec, as follows:

`v = (d)/(t)\\`

v = velocity of electron = ?

d = distance between plates = 2 cm = 0.02 m

t = time elapsed = 1.5 x 10⁻⁸ s

Therefore, using these values in the equation, we get:

`v = (0.02\ m)/(1.5\ x\ 10^(-8)\ s)\\\\v = 1333333.33\ m/s`

Now, we convert this to million m/s:

`v = (1333333.33\ m/s)(1\ million\ m)/(100000\ m)\\\\v =13.3\ million\ m/s`

Therefore, the correct answer is:

A. 13.3