A Car of mass 1000kg applies a constant 200N breaking force over a distance of 30m and comes to a complete stop. How fast was the car going the instant the brakes were engaged.

Before we start we should have some idea of the route of our solution. We should observe that force, distance and work have a relation and that mass, velocity and work have a relation. So we should calculate the work done by the brakes stopping the car. W=FD so W = 20030=6000J We know work = change in energy and that the final energy is 0. So we now know that the starting energy of the car KE = 6000J We now look to the kinetic energy equation that states KE = 1/2 * m * v^2 solving for v we have v=sqrt(2KE/m) we now just plug in v = sqrt(26000/1000) = sqrt(12) = 3.46 ms^-1

SO
Answered by Sean O. Physics tutor

3231 Views

See similar Physics GCSE tutors

Related Physics GCSE answers

All answers ▸

When a toothbrush is charging, p.d. across the primary coil is 230 V, p.d. across the secondary coil is 7.2 V. The primary coil in the charging base has 575 turns of wire on its coil. Find the number of turns on the secondary coil inside the toothbrush.


A note was played on a a keyboard. The frequency of the note was 440 Hz. (a) What does a frequency of 440 Hz mean? (b) The sound waves produced by the keyboard travel at a speed of 340 m/s. Calculate the wavelength of the note.


What does Newton's First Law mean?


How to i calculate total resistance in a circuit?


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences