# l?pid=564.

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Momentum in Football Two football players collide in a play. What type of collision is it?

Momentum in Football Two football players collide in a play. What type of collision is it? Its an inelastic collision. They dont bounce off each other, they stick together.

During a play, this happens several times. Here are some masses and velocities. What will the final velocity of each group be? Which offensive players could be in a position to score?

Sample Problem 1 7 kg v = 0 700 m/s A rifle fires a bullet into a giant slab of butter on a frictionless surface. The bullet penetrates the butter, but while passing through it, the bullet pushes the butter to the left, and the butter pushes the bullet just as hard to the right, slowing the bullet down. If the butter skids off at 4 cm/s after the bullet passes through it, what is the final speed of the bullet? (The mass of the rifle matters not.) 35 g 7 kg v = ? 35 g 4 cm/s continued on next slide

Sample Problem 1 (cont.) 7 kg v = 0 700 m/s 35 g 7 kg v = ? 35 g 4 cm/s p before = 7 (0) + (0.035) (700) = 24.5 kg · m /s Let choose left to be the + direction & use conservation of momentum, converting all units to meters and kilograms. p after = 7 (0.04) + 0.035 v = 0.28 + 0.035 v p before = p after 24.5 = 0.28 + 0.035 v v = 692 m/s v came out positive. This means we chose the correct direction of the bullet in the after picture.

Hockey puck A moves to the right at 50 m/s. It strikes an identical hockey puck B that is stationary on the ice. After the collision, the velocity of A is 35 m/s, 27.6°. What is the velocity of B?

Ans: 24.97 m/s, @ 319°

Problem A 0.552 kg sparrow is flying at a speed of 3.68 m/s at a heading of 37.9 o N of E. It is grabbed by a 21.72 kg eagle flying at a speed of 45.57 m/s at a heading of 28.36 o N of E. What is the speed of the predator & prey together immediately after the capture?

Problem A 0.552 kg sparrow is flying at a speed of 3.68 m/s at a heading of 37.9 o N of E. It is grabbed by a 21.72 kg eagle flying at a speed of 45.57 m/s at a heading of 28.36 o N of E. What is the speed of the predator & prey together immediately after the capture? 44.53 m/s