1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Braking motorcycle

  1. Nov 25, 2013 #1
    A motorcyclist sees an obstacle and comes to a complete stop. Given are reaction time (0.8seconds), acceleration once started braking (-6.5meters/seconds^2), and total distance traveled (35meters) from initial sighting to complete stop. Solve to find initial velocity and time from when he started braking to when he stopped.

    I can't figure out a single formula to use that will help me find one of the unknowns and solve the problem! Please help!
  2. jcsd
  3. Nov 25, 2013 #2


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    You must know some equations relating to uniform acceleration. (The acronym SUVAT is often used.)
  4. Nov 25, 2013 #3


    User Avatar

    Staff: Mentor

    Neither can I ! Certainly not until I have first condensed the wordy problem sentences into a familiar mathematical form, e.g.,

    vf = 0 m/sec
    reaction time t = 0.8 secs
    total distance d = 35m

    vi = ?? m/sec

    That done, the next step is to write down all the equations of motion that you know. Then go through them one by one, ticking off the variables you know or need, until you have highlighted by multiple ticks some likely candidates to use for solving this.
  5. Nov 26, 2013 #4
    Suppose you did know the speed of the motor cyclist. call it v. Could you compute the distance traveled during the reaction time, and the distance traveled when breaking?
    Set the stopping distance equal to the sum of those two distances and solve for v.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted

Similar Discussions: Braking motorcycle
  1. Emergency braking (Replies: 1)

  2. Motorcycle Wheels (Replies: 1)

  3. Braking Speed (Replies: 5)

  4. A Truck Braking (Replies: 15)