How Do You Calculate Work and Distance in These Physics Problems?

AI Thread Summary
To calculate the distance a car travels while braking, one must apply the work-energy principle, using the average force and mass to determine acceleration and then distance. For the runner, the work done can be calculated using the change in kinetic energy, factoring in both the increase in speed and the opposing force of friction. It is essential to show all calculations step-by-step to facilitate assistance. Understanding the relationship between force, mass, and acceleration is crucial in solving these physics problems. Clear calculations and application of formulas are necessary for accurate results.
moela
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1. A car changes velocity from 25m/s to 8.0m/s. If the average force applied to the brakes is 16000N, how far does the 2300kg car go in this time?

2. How much work is done if a 75kg runner speeds up from 1.2 m/s to 4.0m/s in 1.7s? How much extra work is done if there is a force of friction against the runner of 26N?
 
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Hey, moela, welcome aboard!

You need to show work before we can help.
 
You can start off by calculating what you can.
For example if you know the mass and the speed what can you find out?
 

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