194,686 views
2 votes
2 votes
A bicyclist is stopped at the entrance to a valley, as sketched below. Where would the bicyclist have the highest potential energy? Where would The bicyclist have the lowest potential energy? Where would bicyclist have the highest kinetic energy? Where would the bicyclist have the highest speed winning? Conversation with the bicyclist’s Kinetic energy be higher at A or B? With a bicycle is potential energy be higher at A or B? What’s a bicyclist total energy we hire at A or B? Supposed to bicyclist lets off the brakes and coast down into the valley without peddling. Even if there was no friction or air resistance to slow her down, what is the farthest point the bicyclist could reach without peddling?

A bicyclist is stopped at the entrance to a valley, as sketched below. Where would-example-1
User Sangbeom Han
by
3.1k points

1 Answer

22 votes
22 votes

Step 1 - Understanding the relation of potential energy, kinectic energy and the conservation of energy

The potential energy is the energy related to a body that can start moving under the influence of a force anytime soon.

The kinf of potential energy depends on the force that could act on the body. When a body is lifted, because gravity can pull it back, we say that this body has gravitational potential energy

Kinetic energy, on the other hand, is related to actual movement. It depends on the mass as well as on the velocity of the body. When we lift an object and drop it next, all the potential energy will be converted to kinetic energy, i.e., the velocity of the object we dropped will be also proportional to the height. It cannot gain more energy.

Step 2 - Interpreting the problem

Now that we know how potential and kinetic energy work, we can start working on the problem. Since potential energy is directly proportional to height, the highest potential energy would be attained at F.

The lowest potential energy, on the other hand, woud be attained at D, i.e., the smaller height.

The highest kinetic energy would be attained when all the potential energy is converted to kinetic energy, i.e., when the bicyclist, starting at A, loses its potential energy reaching D

The speed is directly proportional to the kinetic energy: the higher the speed, the higher the kinetic energy. Since the kinetic energy, as we saw, is the greatest at D, the velocity will also be the greatest at this point.

User Dieend
by
2.9k points