Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Bat hits baseball

Tags:
  1. Oct 24, 2014 #1
    << Moderator Note -- thread moved to the HH forums >>

    a pitcher throws a 1.5kg baseball with speed 25m/s. it hits the bat and return in opposite direction with same speed. the force that bat exerted on ball is 50N. For how long was the bat touching(in contact) the ball? I used: delat t * F = m*delta velocity delta t 50N = 1.5(25-(-25)) and i got t=1.5 s. Is it correct? It does not seem like.
     
    Last edited by a moderator: Oct 24, 2014
  2. jcsd
  3. Oct 24, 2014 #2
    That's a pretty happy baseball. Are you sure of that 1.5 kg?

    Chet
     
  4. Oct 24, 2014 #3
    yes
     
  5. Oct 24, 2014 #4
    A major league baseball has a mass of 5.25 oz (0.15 kg). That 1.5 kg is an obvious typo.

    And, please, don't try to play baseball with a 1.5 kg baseball. If you got hit by a fastball, it would be "lights out."

    Chet
     
  6. Oct 24, 2014 #5
    o
    ok, but under the conditions described what would be time?
     
  7. Oct 24, 2014 #6
    If you are asking whether you solved the problem correctly, given the obviously faulty data, then the answer is yes.

    Chet
     
  8. Oct 28, 2014 #7
    force is the rate of change of momentum.
    Thus, you have been given the change in momentum, the force excerted.
    So,
    t=Change in momentum/force
    =2*1.5*25/50=75/50=1.5

    Yup, your answer is correct
     
  9. Oct 28, 2014 #8

    sophiecentaur

    User Avatar
    Science Advisor
    Gold Member

    This is the sort of question you have to answer on impulse. Boom boom.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook