An Electron's Velocity Calculation

Problem:

An electron has a constant acceleration of 3.2 m/s². At a certain instant its velocity is 9.6 m/s. What is its velocity 2.5 sec earlier?

Options:

A) 1.4 m/s

B) 1.6 m/s

C) 2.4 m/s

D) 3.2 m/s

Final answer:

The velocity of the electron 2.5 seconds earlier is 1.6 m/s.

Explanation:

To find the velocity of the electron 2.5 seconds earlier, we can use the equation:
v = u + at
Where:
v is the final velocity
u is the initial velocity
a is the acceleration
t is the time

Given that the acceleration is constant at 3.2 m/s² and the final velocity is 9.6 m/s, we can plug in these values to find the initial velocity:

9.6 m/s = u + (3.2 m/s²)(2.5 s)

Simplifying this equation gives:

u = 9.6 m/s - (3.2 m/s²)(2.5 s) = 9.6 m/s - 8 m/s = 1.6 m/s

Therefore, the velocity 2.5 seconds earlier is 1.6 m/s.