Answer:
8.08 x 10^-5 m
Explanation:
A = 2 mm^2 = 2 x 10^-6 m^2
Total number of electrons, N = 9.4 x 10^18
time, t = 3 s
n = 5.8 x 10^28 electrons/ m^3
Current, i = Q / t = N x e / t = (9.4 x 10^18 x 1.6 x 10^-19) / 3 = 0.5 A
Let vd be the drift velocity.
i = n e A vd
0.5 = 5.8 x 10^28 x 1.6 x 10^-19 x 2 x 10^-6 x vd
vd = 2.7 x 10^-5 m/s
Distance traveled by the electrons = velocity x time
= vd x t = 2.7 x 10^-5 x 3 = 8.08 x 10^-5 m
A = (v - u) / t
a = acceleration
v = final velocity
u = initial velocity
t = time
45 = (v - 300) / 10
45 × 10 = v - 300
450 + 300 = v
v = 750 m/s
Hope this helps!
P.S. Let me know if you need an explanation
Time=speed/acceleration
Gravitaional Acceleration=9.8 m/s^2
Speed=24.5 m/s
Time=24.5/9.8=2.5 s
Force=A×M
10m/s×0.20kg
=2Newton