Physics - Center of Mass

posted by .

A baseball player uses a bat with mass mbat to hit a ball with mass mball. Right before he hits the ball, the bat's initial velocity is 36 m/s, and the ball's initial velocity is -20 m/s (the positive direction is along the positive x-axis). The bat and ball undergo a one-dimensional elastic collision. Find the speed of the ball after the collision. Assume that mbat is much greater than mball, so the center of mass of the two objects is essentially at the bat.

  • Physics - Center of Mass -

    u=36 m/s, v(o)= -20 m/s.
    Imagine that the bat is at rest, and the ball is approaching to it at the releative velocity
    v(x)= v(o)+u =20+36 =56 m/s.
    Then in the bat’s frame of reference the ball bounces at the velocity 56 m/s directed in opposite direction. The velocity of the ball in the rigid frame is the sum of the relative velocity of the bounce and velocity of the moving frame of reference.
    The projections on the x-axis;
    v(x) = 2u(x) –v(ox),
    u(x) = u.
    v(ox) = -v(o) ,

    v(x) = 2u+v(o)

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Physics

    Baseball player A bunts the ball by hitting it in such a way that it acquires an initial velocity of 1 m/s parallel to the ground. Upon contact with the bat, the ball is 1.5 m above the ground. Payer B wishes to duplicate this bunt, …
  2. physics

    A bat hits a moving baseball. If the bat delivers a net eastward impulse of 0.7 N-s and the ball starts with an initial horizontal velocity of 3.8 m/s to the west and leaves with a 5.2 m/s velocity to the east, what is the mass of …
  3. Physics

    A baseball player hits a home run that just barely clears the 12m high fence in right field, 94m from home plate. If the ball was at a height of 1m when hit, and its initial path after it left the bat was at an angle of 35 degrees …
  4. Physics

    A baseball player hits a home run that just barely clears the 12m high fence in right field, 94m from home plate. If the ball was at a height of 1m when hit, and its initial path after it left the bat was at an angle of 35 degrees …
  5. physics

    A ballplayer standing at homeplate hits a baseball that is caught by another player at the same height above the ground from which it was hit. The ball is hit with an initial velocity of 23.0 m/s at an angle of 58.0° above the horizontal. …
  6. Physics

    Baseball player A bunts the ball by hitting it in such a way that it acquires an initial velocity of 1.3 m/s parallel to the ground. Upon contact with the bat, the ball is 1 m above the ground. Payer B wishes to duplicate this bunt, …
  7. Physics!

    Baseball player A bunts the ball by hitting it in such a way that it acquires an initial velocity of 1.9 m/s parallel to the ground. Upon contact with the bat, the ball is 1.5 m above the ground. Payer B wishes to duplicate this bunt, …
  8. physics

    the instant before a batter hits a 0.14 kilogram baseball, the velocity of the ball is 45 m/s west. the instant after the batter hits the ball, the ball's velocity is 35 m/s. The bat and ball are in contact for 1.0*10^-2. 1. determine …
  9. physics

    A ballplayer standing at homeplate hits a baseball that is caught by another player at the same height above the ground from which it was hit. The ball is hit with an initial velocity of 23.0 m/s at an angle of 54.0° above the horizontal. …
  10. Physics

    Baseball player A bunts the ball by hitting it in such a way that it acquires an initial velocity of 2.0 m/s parallel to the ground. Upon contact with the bat the ball is 1.0 m above the ground. Player B wishes to duplicate this bunt, …

More Similar Questions