Question

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?

1) 5 x 10-10 W
2) 1 x 10-8 W
3) 2 x 10-5 W
4) 8 x 10-5 W

Answer 1

The power exerted by electrical forces on the fragment of fiber is 1.6 x 10^-3 W.

Step-by-step explanation:

To find the power exerted by electrical forces on a fragment of fiber, we can use the equation:

Power (P) = Force (F) x Velocity (v)

First, we need to calculate the force exerted by the electrical forces. The force can be calculated using Newton's second law:

Force (F) = mass (m) x acceleration (a)

As the fragment of fiber is accelerating due to the electrical forces, we can use the equation:

Force (F) = mass (m) x change in velocity (Δv) / time (t)

Plugging in the values, we have:

Force (F) = 0.04 g x (200 mm/s - 0) / (10 ms - 0)

Converting the units to kilograms and seconds, we get:

Force (F) = 0.04 x 10^-3 kg x (200 x 10^-3 m/s) / (10 x 10^-3 s)

Calculating this, we find:

Force (F) = 8 x 10^-3 N

Now, we can calculate the power:

Power (P) = Force (F) x Velocity (v)

Power (P) = 8 x 10^-3 N x 200 x 10^-3 m/s

Calculating this, we find:

Power (P) = 1.6 x 10^-3 W