How Much Energy Was Lost to Friction When Braking Downhill?

Click For Summary
SUMMARY

The discussion centers on calculating the energy lost to friction when an 800kg car coasts down a 40m hill, starting at a speed of 6m/s and ending at 20m/s. The formula used is based on the conservation of energy principle: initial kinetic energy plus potential energy equals final kinetic energy plus energy lost to friction. The initial potential energy is calculated as 31,200 Joules, and the initial kinetic energy is 144 Joules. The final kinetic energy at the bottom of the hill is 1,600 Joules, leading to a total energy loss to friction of 30,744 Joules.

PREREQUISITES
  • Understanding of kinetic energy calculations
  • Knowledge of potential energy concepts
  • Familiarity with the conservation of energy principle
  • Basic algebra for solving equations
NEXT STEPS
  • Study the principles of energy conservation in physics
  • Learn about kinetic and potential energy formulas
  • Explore real-world applications of friction in automotive engineering
  • Investigate advanced topics in energy loss during braking
USEFUL FOR

Students studying physics, automotive engineers, and anyone interested in the mechanics of energy transfer and friction in vehicles.

davedave
Messages
50
Reaction score
0
All my friends got different answers to the problem below. What is your answer?

An 800kg car moving at 6m/s begins to coast down a hill 40m high with its engine off. The driver applies the brakes so that the car's speed at the bottom of the hill is 20m/s. How much energy was lost to friction?
 
Physics news on Phys.org
Kinetic energy_start + potential energy = kinetic energy_end + friction
 

Similar threads

Is the Hertzian Contact Model Suitable for Simulating Car Braking on Wet Roads?
  • · Replies 4 ·
Replies
4
Views
2K
Physics homework help regarding energy and friction
  • · Replies 4 ·
Replies
4
Views
2K
How Does Braking Compare to Turning in Avoiding Collisions?
  • · Replies 9 ·
Replies
9
Views
2K
Kinetic energy & Conservation of energy
  • · Replies 17 ·
Replies
17
Views
2K
Finding Frictional Force and Power Using Work and Energy
  • · Replies 4 ·
Replies
4
Views
3K
Wow much thermal energy was generated by friction?
  • · Replies 5 ·
Replies
5
Views
8K
How Do You Calculate Frictional Force in a Braking Scenario?
  • · Replies 2 ·
Replies
2
Views
1K
Force of Friction: Stopping 1,000kg Car at .8 Coeff.
  • · Replies 2 ·
Replies
2
Views
2K
The Work of Friction: Explained in .32m
  • · Replies 8 ·
Replies
8
Views
2K
How Fast Was Car A When It Hit Car B?
  • · Replies 8 ·
Replies
8
Views
8K