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!

Homework Help: Need Help with Momentum and Impulse? Need some one smart

  1. Nov 27, 2008 #1
    Need Help with Momentum and Impulse?!?! Need some one smart......

    The only formulas that were provided were

    1. I =Δp
    2. mΔv
    3. I=FΔt
    4. KE= 1/2 mv^2
    5. PE= mgΔh
    6. ΔPE= ΔKE
    7. W= F*D
    8. W= ΔKE

    Momentum Before Collision = Momentum After Collision

    9. m`av`a + m`bv`b = m`av`a + m`bv`b Elastic Collision
    10. m`av`a + m`bv`b = m`av`b(v) inelastic collision

    The little apostrophe are for subscripts, e.g. m`a, meaning "m" is normal, but the a is a subscript.

    1. A tennis ball may leave the racket of a top player on the serve with a speed of 65 m/s. If the ball's ,*** is .06 kg and it is in contact with the rackt for .03 secs, what is the average force on the ball?

    2. A .145 kg basball pitched at 39 m/s is hit on a horzontal line drive straight back towards the pitcher at 52 m/s. If the contact time betwween bat and ball is 1.00 E-3 sec, calculate the average force between the bat and ball contact.
  2. jcsd
  3. Nov 27, 2008 #2
    Re: Need Help with Momentum and Impulse?!?! Need some one smart......

    1) You know the ball starts off at rest, and is then given a hit, which leads to a change in momentum. Impulse is a change in momentum; substitute and use that with the impulse formula to solve for force.

    2)Yet again, solve for the change in momentum. Once found, set equal to I=FΔt
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook