On this day in physics: 04 February 1600- Johannes Kepler begins work with Tycho Brahe. Tycho Brahe was one of the most prolific astronomers of all time, and had years and years of astronomical data. Johannes Kepler had the mathematical know how and intrigue to take this wealth of data and transform it into Kepler's Planetary laws of motion, which describe how planets move around the Sun.
Word of the Day: Centrifugal Force- A centrifugal force is what is known as a "fictitious" or "false force" experienced by objects undergoing some sort of curved motion or circular motion. When turning in a circle, the object experiences the sensation of an outward force. Imagine your clothes in the dryer going through the final spin. All of the clothes stick to the outside of the dryer, spinning in a circle. It is possible to experience this sensation on many amusement park rides. The force is so strong that on some rides, while spinning at a certain rate, the floor can be lowered or removed, and riders will be pushed to the outside rim of the ride. Imagine swinging a ball on a string in a circle. In this scenario, the only force truly acting on the ball is the tension of the string pulling inwards. However, the ball is not flying outwards, so there must be a balancing force. This is the centrifugal force at work. This is what allows centrifuges to sort matter by density, or what causes the remnants of an almost empty ketchup jug to move to the nozzle when you swing it in a circle.
Quote of the Day: "The fact that mankind persists shows that the cohesive force is greater than the disruptive force, centripetal force greater than centrifugal." -Ghandi
Keywords: Centrifugal, Force, Acceleration, Curve, Circular, Motion.
