A 10.0 -kg toy motorized boat uses 2.0 W of power, has a constant acceleration from rest and re speed in 10 s on a horizontal surface What was that final speed? [T4]

Here's how to solve this problem:<br /><br />1. **Find the work done:** Power is the rate of doing work (P = W/t). Therefore, Work (W) = Power (P) * time (t) = 2.0 W * 10 s = 20 J<br /><br />2. **Relate work to kinetic energy:** The work done on the boat results in a change in its kinetic energy. Since it starts from rest, the initial kinetic energy is zero. Therefore, the final kinetic energy (KE) is equal to the work done (W). So, KE = 20 J<br /><br />3. **Use the kinetic energy formula:** Kinetic energy is given by KE = (1/2)mv², where m is mass and v is velocity. We know KE = 20 J and m = 10.0 kg.<br /><br />4. **Solve for the final speed (v):**<br /> 20 J = (1/2) * 10.0 kg * v²<br /> 40 J = 10.0 kg * v²<br /> v² = 4 m²/s²<br /> v = 2 m/s<br /><br />Therefore, the final speed of the boat is $\boxed{2 m/s}$.<br />