Assuming a mass of 0.04 g, what is the power exerted by the electrical forces on a fragment of fiber if the fragment has a velocity of 200 mm/s, 10 ms after ejection?

To solve this problem, we need to use the formula for power, which is work done per unit time.

Step 1: Convert the given values to SI units. Mass (m) = 0.04 g = 0.04 x 10^-3 kg Velocity (v) = 200 mm/s = 200 x 10^-3 m/s Time (t) = 10 ms = 10 x 10^-3 s

Step 2: Calculate the kinetic energy (KE) of the fragment using the formula KE = 1/2 mv^2. KE = 1/2 * 0.04 x 10^-3 kg * (200 x 10^-3 m/s)^2 KE = 0.0008 Joules

Step 3: Calculate the work done (W) which is equal to the change in kinetic energy. Since the fragment starts from rest, the initial kinetic energy is zero. So, the work done is equal to the final kinetic energy. W = KE = 0.0008 Joules

Step 4: Calculate the power (P) using the formula P = W/t. P = 0.0008 Joules / 10 x 10^-3 s P = 0.08 Watts

So, the power exerted by the electrical forces on the fragment of fiber is 0.08 Watts.