Practice applying physics ideas to sports, including impulse, momentum change, spin effects, air resistance, and projectile motion.
Read each problem carefully. Show your work when calculations are needed. Use complete sentences for explanations.
Explore how forces, contact time, spin, and launch angle affect sports motion
Physics - Grade 6-8
- 1
A soccer player kicks a still ball. The ball has a mass of 0.45 kg and leaves the foot moving at 20 m/s. What is the ball's change in momentum?
- 2
A tennis racket is in contact with a ball for 0.005 seconds. During that time, the ball's momentum changes by 4 kg m/s. What average force does the racket apply to the ball?
- 3
Two baseball players hit identical balls so that each ball has the same change in momentum. Player A's bat touches the ball for 0.002 seconds. Player B's bat touches the ball for 0.004 seconds. Which player applies the smaller average force, and why?
- 4
A goalie catches a fast hockey puck by moving the glove backward as the puck enters it. Explain how this reduces the force on the goalie's hand.
- 5
A basketball player gives a ball backspin during a shot. Describe one way backspin can affect how the ball bounces or rolls when it hits the rim or backboard.
- 6
A golfer hits a ball with backspin. The spinning ball can experience an upward lift force from the air. How might this affect the ball's flight compared with a ball that has little spin?
- 7
A soccer player kicks the side of a ball, giving it spin. The ball curves in the air. What is the name of the effect that can make a spinning ball curve, and what causes the curve?
- 8
A football is thrown with a tight spiral. Explain why spin can make the football's flight more stable.
- 9
A runner pushes backward on the ground with a force of 600 N for 0.20 seconds during one step. What impulse does the runner give to the ground during that push?
- 10
During a long jump, an athlete wants to leave the ground with a large speed. Explain why pushing hard against the ground for as long as possible during takeoff can help.
- 11
A ball is launched from the ground at the same speed in three different directions: low angle, medium angle, and straight up. Which launch will likely travel the farthest horizontally if air resistance is small: low angle, medium angle, or straight up? Explain.
- 12
A basketball shot has too little arc and hits the front of the rim. What change could the player make to the launch angle to give the ball a better chance of going in?
- 13
A baseball is hit horizontally from a tee. At the same instant, another identical baseball is simply dropped from the same height. If air resistance is ignored, which ball hits the ground first?
- 14
In real sports, air resistance is often important. Name one sport where air resistance strongly affects the motion of the ball or object, and explain how.
- 15
A coach says, "Follow through after you hit the ball." Use impulse to explain why a good follow-through can help in sports such as tennis, golf, or baseball.