1) Category: Natural
Title: Dribble Dribble
Physics Concept: Action/Reaction
Description of Photo: In this photo, my brother is dribbling a basketball similar to how one would do so when he or she is playing basketball. When my brother dribbles the ball, he hits the ball towards the ground repeatedly as a way of moving the ball.
Explanation of Physics: Since the ball is made of rubber, if he bounces the ball on the ground with a strong force, the ball will come up with a strong force as well. There are many ways for a player to control his or her dribbling to make sure that the ball does not move too far out of reach. First, he or she can bounce the ball at a force that keeps the ball at waist height. This ideology corresponds well with Newton's third law of an action with an equal and opposite reaction. My brother exerts an applied force on the ball. In contrast, when the ball hits the ground, the normal force of the ground exerts itself on the ball. This action and subsequent reaction, causes the ball to bounce.
2) Category: Contrived
Title: Parachuting His Way to Victory
Physics Concept: Freefall/Projectile Motion
Description of Photo: In this photo, I tied a small parachute that I found in my house and tied it to one of my old action figures. I did this in order to show the effects of freefall motion since I could not go skydiving.
Explanation of Physics: The physics in this photo is almost synonymous with the subjects of freefall and projectile motion. In freefall, an object falls to the earth with an acceleration of -9.8 m/s^2. Since the action figure has a parachute attached to it, it reaches the earth much slower than if it had no parachute. However, one can still learn the effects that a parachute has on the rate at which an object falls to the earth. In addition, this photo can shed light on the subject of projectile motion. A projectile is an object thrown into space by the exertion of force. Due to the fact that the action figure was dropped, it is indeed a projectile.
Title: No Lift, Just Drag
Physics Concept: Friction
Description of the Photo: In this photo, my brother attempts to drag this chair across the room. He knows that it is heavy, so he has to figure out some mechanism to do it effectively.
Explanation of Physics: When my brother drags the chair across the floor, he knows that he wants as little friction as possible to make the drag easy. In other words, he wants a low friction coefficient so that he does not have to exert a lot of force on the chair. He is already at a disadvantage because the carpet has a higher friction coefficient than the carpet. Therefore in order to decrease the friction, he tilts the chair so that only two of the legs touch the floor instead of four. Also, it is very hard to first start moving the chair due to the high static friction which comes with making the chair move. After, the kinetic friction will be much less than the static friction allowing easy movement. In order for the chair to move, my brother must exert a stronger applied force to move the chair to overcome the kinetic friction.
Title: Flying High, The Limit is The Sky
Physics Concept: Center of Mass
Description of Photo: In this photo, my friend Darius is attempting to jump over a bar in high jump that is 6 feet 11 inches in the air. He was successful!
Explanation of Physics: I, a fellow high jumper, know that there is a significant amount of physics involved in the high jump most of all. First, for Darius to get up that high he has to take off the ground with a significant amount of force. He also has to twist his body from moving sideways to moving vertically. Also, for most humans, their center of mass is located near their navel region. In Darius' exquisite high jump form, he makes sure to rotate his hips upward so that his center of mass is technically under the bar allowing the rest of his body to clear the bar afterwards.
Title: Technique of the Shot
Physics Concept: Force/ Kinetic Energy
Description of Photo: In this photo, my brother attempts a basketball shot. He follows the elements of a good shot perfectly.
Explanation of Physics: The shot in basketball is stuffed with physics that contribute to the ball going into the net. In this photo in particular, my brother needs to jump into the air in order to give him a better trajectory. So he exerts force on the ground to launch himself in the air. Next, when he is shooting, he needs the force in his arms to propel the ball towards the basket. Therefore, he winds his elbow back (which is his potential energy) so that when his elbow extends, its kinetic energy will cause the ball to travel towards the basket. Also, the force in which he propels the ball has a huge effect on whether or not the ball goes in. Since force equals mass times acceleration, he must accelerate the ball off his fingers well to use the correct force to make the ball enter the basket.
