Results 1 to 2 of 2

Math Help - question!

  1. #1
    Newbie
    Joined
    Jun 2006
    Posts
    5

    question!

    In an emergency stop to avoid an accident, a shoulder-strap seat belt holds a 60-kg passenger firmly in place. If the car were initially traveling at 90 km/h and came to a stop in 5.5 s along a straight, level road, what was the average force applied to the passenger by the seatbelt?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Joined
    Oct 2005
    From
    Earth
    Posts
    1,599
    First thing is convert all units to standard ones.

    \frac{90 km}{h} \times \frac{1000m}{1km} \times \frac{1h}{60min} \times \frac{1min}{60sec}=\frac{25m}{sec}

    So if F_{net}=ma then we need to solve for acceleration since we have the mass. Use the equation v_{f}=v_{0}+at. Plugging in your values shows 0=25+5.5a and a=4.55 m/s^2.

    This is the average acceleration, thus the average force is 4.55*60=273N
    Follow Math Help Forum on Facebook and Google+

Search Tags


/mathhelpforum @mathhelpforum