Posted by **John** on Monday, February 25, 2008 at 2:32pm.

A power boat of mass 495 kg is cruising at a constant speed of 8.9 m/s. The propeller provides a drive force of 780 N. The driver of the boat shuts off the engine, and the boat coasts to a halt. Assume-contrary to fact-that the resistive force due to the water is constant, independent of the boat's speed.

(a) How far does the boat coast?

m

(b) How much time does it take for the boat to come to rest after the engine is turned off?

- Physics -
**drwls**, Monday, February 25, 2008 at 3:06pm
a) Set F*X equal to the initial kinetic energy and solve for X. X is the distance and f is the friction force, which is here assumed to equal the propeller force while running at full speed, 780 N

b) Divide X by the average speed, V/2.

## Answer this Question

## Related Questions

- physics - A power boat of mass 465 kg is cruising at a constant speed of 8.9 m/s...
- Physics - A power boat of mass 460 kg is cruising at a constant speed of 8.9 m/s...
- physics - A power boat of mass 460 kg is cruising at a constant speed of 8.9 m/s...
- Physics - A power boat of mass 475 kg is cruising at a constant speed of 8.9 m/s...
- Physics - A 1250 kg boat is traveling at 90 km/h when its engine is shut off. ...
- Physics - A 1250 kg boat is traveling at 90 km/h when its engine is shut off. ...
- Physics - A 1250 kg boat is traveling at 90 km/h when its engine is shut off. ...
- math - A particular power boat travelling at V0 km/h when its power is turned ...
- Math - 12. A particular power boat travelling at V0 km/h when its power is ...
- physics - A 1000 kg boat is traveling at 90 km/h when its engine is shut off. ...