Top 10 Physics Blog

10: Tides
I had always wondered how the tides worked and why they changed the way they did, and now I know that it is because of the differences in gravitational forces caused by the moon and NOT the sun. Neap tides are when the moon and sun are at perpendicular sides of the earth, and these make for less severe highs and lows, while a Spring tide occurs when the sun and moon are in a line, this makes for higher highs and lower lows.

9: Stoplights
Many times I had been sitting at a stoplight in my car wondering how a stoplight knows that a car is there. With knowledge of electromagnetism, I can now see how the everyday stoplights work, and understand how genius the design is. When a car moves over coils of wire that are embedded in the ground, then the car amplifies the magnetic field of the earth, therefore inducing a voltage and a current in the wires. This current is read by a computer which tells the stoplight that a car is waiting.

8: Trajectory/ Thrown Objects
This lesson applies heavily to my life as a football player and the trajectory/ flight path of the football when thrown. Since all objects are acted upon by gravity, the flight path of a thrown object will be a parabola, the object will be at the same height twice in its flight path.

7: Momentum
This lesson was fun to learn because it let me know that mass isn't everything when it comes to momentum. For example a smaller football player can have more momentum than a larger player moving slower. Momentum = mass x velocity, therefore if a smaller object is moving really really fast then it will have a greater momentum than a slow moving large object.

6: Energy
The concept of transferring kinetic energy to potential energy was a fun one to learn. Kinetic Energy is the energy of motion, and can be found by KE= 1/2mv^2. Potential energy is equal to Mass x gravity x height or mgh. Energy can never be created or destroyed so one type of energy must transfer to the other. For example when an object is swung from a pendulum, it starts off not moving with only potential energy, but when it it starts moving some of its potential energy is transferred into kinetic energy.

5: Tangential vs Rotational motion
The difference between tangential and rotational motion can be seen in my life at track meets very frequently and is fun to think about. Tangential motion is the distance covered in a given amount of time by a rotating object, for example a gear might cover 12 prongs in 30 seconds. Rotational motion is the amount of rotations per given time, for example 3 rotations in 40 seconds.

4: Skydiving
Learning about skydiving was an interesting topic to learn and I had fun thinking about why air resistance works the way it does. When skydiving, your acceleration will only decrease from the point when you jump out of the plane or helicopter, but you keep speeding up until your air resistance equals your weight, this is called Terminal Velocity. Terminal Velocity is the fastest that an object can physically fall.

3: Rotational Inertia
Learning about rotational inertia was fun to learn about because you can see examples of it in life such as ice skating and rotating on a chair. Rotational Inertia is the tendency of an object to resist angular motion, the higher the rotational inertia, the harder it will be to start or stop rotating the object. Rotational inertia is based on an object's mass, and the distribution of said mass.

2: Conservation of Momentum
The conservation of momentum was fun to learn because I had always wondered why if you caught a ball on a frictionless surface then you would slide. Momentum will always be conserved in a system, and when you catch a ball, the momentum from the movement of the ball must be conserved and transferred into you.

1: Airbags
Learning how airbags keep us safe was really fun! Since Airbags increase the time over which your head or body is stopped, there will be less of a force on your body. This is because your body undergoes the same impulse to stop regardless of how you are stopped. Impulse = Force x time. Less force on your body means less chance for injury!