An electron, starting from rest and moving
with a constant acceleration, travels 4.7 cm in
5.2 ms.
What is the magnitude of this acceleration?
Answer in units of km/s2
To find the magnitude of acceleration, we can use the following equation:
d = (1/2) * a * t^2
Where:
d = displacement
a = acceleration
t = time
In this case, the electron travels a distance of 4.7 cm in 5.2 ms. We need to convert these values to the SI units (meters and seconds) before calculating acceleration.
1 cm = 0.01 m
1 ms = 0.001 s
So, the displacement (d) becomes:
d = 4.7 cm * 0.01 m/cm = 0.047 m
And the time (t) becomes:
t = 5.2 ms * 0.001 s/ms = 0.0052 s
Now, we can rearrange the equation to solve for acceleration:
a = (2 * d) / t^2
a = (2 * 0.047 m) / (0.0052 s)^2
a = 18.0769231 m/s^2
Lastly, we can convert the acceleration to km/s^2:
1 km = 1000 m
a = 18.0769231 m/s^2 * (1 km / 1000 m)^2
a = 0.0180769231 km/s^2
Therefore, the magnitude of acceleration is approximately 0.018 km/s^2.