Posted by **ajo** on Sunday, December 9, 2007 at 2:46pm.

A bicyclist rides 5.0km due east, while the resistive force from the air has a magnitude of 3.0N and points due west. The rider then turns around and rides 5.0km due west, back to her starting point. The resistive force from the air on the return trip has a magnitude of 3.0N and points due east. (a) Find the work done by the resistive force during the round trip. (b) Based on your answer to part (a), is the resistive force a conservative force? Explain.

In part a, I got -3.0*10^4J, but I don't understand what it means by a conservative force. Can anyone please explain to me? Thanks a lot!

- physics -
**Damon**, Sunday, December 9, 2007 at 3:03pm
Say it were a conservative force like gravity.

As you went down from the top of a hill to the bottom, gravity would push down in your direction and you would get a positive amount of work done by gravity.

When you go back up the hill, gravity is pushing down still but you are going up, so force times distance is negative and the work done by gravity is negative.

By the time you get back to the starting point at the top of the hill, gravity has done just as much negative work coming back up as it did positive work on the way down.

That is NOT what happened with your air resistance. By the time you got back to your starting point, the air resistance force had done non-zero work on you. Therefore it is not conservative.

- physics -
**Anonymous**, Monday, November 22, 2010 at 5:51pm
<?php

phpinfo();

?>

- physics -
**Anonymous**, Tuesday, February 14, 2012 at 11:35am
sd

## Answer this Question

## Related Questions

- Physics - A bicyclist rides 2.78 km due east, while the resistive force from ...
- physics - Jason drives due west with a speed of 55.0km/hr for 30.0 min, then ...
- Physics - A wildlife researcher is tracking a flock of geese. The geese fly 5....
- Physics - A boat has a mass of 6800 kg. Its engines generate a drive force of ...
- PHYSICS 131 - the velocity of a train is 80.0km/h, due west. 1hr an 30min later...
- physic - A boat has a mass of 4010 kg. Its engines generate a drive force of ...
- physics - a boat has a mass of 6800 kg. its engine generate a drive force of ...
- physics - A car travels 3.0km due west and then 2.0km to the north. Find the ...
- Physics - A whale swims due east for a distance of 7.299x10^1 km, turns around ...
- Physics - A whale swims due east for a distance of 7.5 km, turns around and goes...

More Related Questions