You know that friction also causes heat. Think about when you rub your hands together. It is friction that makes them warm. But why does this happen? Friction causes the molecules on rubbing surfaces to move faster. Faster moving particles have more heat energy. Heat from friction can be useful. Can you think of other places where you might find friction? Friction also lets you light a match. Heat from friction can also cause problems. It can cause a car to overheat. To reduce friction, oil is added to the engine. Oil coats the surfaces of moving parts. This coating of oil makes them slippery. When things are slippery there is less friction. Have you ever seen a sign that says, slippery when wet? This too has to do with friction. Water, like oil, can reduce friction. The wet surface may allow your shoes to slide more easily.

Why do rubbing your hands make them warm?

Patricia Cross and her boyfriend Larry Osborne , two students in a San Francisco school , become expelled for the publication of an off-campus underground paper . As a result , a philosophy professor , Dr. Jonathon Barnett , resigns his teaching position and decides to become an advocate for the counterculture youth movement and , specifically , the use of LSD . The hippies of the Haight-Ashbury district first see him as a hero and then as something even more . Dr. Barnett even makes an appearance on the Joe Pyne TV show to voice his support of the hippie community and the use of LSD . One scheming young man sees the opportunity to build Dr. Barnett as the head of a cult centered around the use of LSD . He hopes to earn profit from the users , Dr. Barnett's speeches known as '' happenings , '' and their lifestyles . At a massive LSD-fueled dance , Patricia begins to have a bad trip Which leads to an argument between her and Pat , ultimately splitting the couple up . After Patricia realizes that she's pregnant , Dr. Barnett advises her to have an abortion , ultimately leading to Patricia attempting suicide . However , Larry saves her and makes the destruction of Dr. Barnett's cult his primary objective . Larry shoots Dr. Barnett from the crowd at one of his massive speeches . As another hippie in attendance calms the audience and Elliot sees his new leader for their cult-like organization , Larry realizes that his assassination of Dr. Barnett simply made him a martyr for the hippie movement .

What does Larry save Patricia from?

The highest point of a wave is the crest. The lowest point is the trough. The vertical distance between a crest and a trough is the height of the wave. Wave height is also called amplitude. The horizontal distance between two crests is the wavelength. Both amplitude and wavelength are measures of wave size. The size of an ocean wave depends on how fast, over how great a distance, and how long the wind blows. The greater each of these factors is, the bigger a wave will be. Some of the biggest waves occur with hurricanes. A hurricane is a storm that forms over the ocean. Its winds may blow more than 150 miles per hour! The winds also travel over long distances and may last for many days.
How do you calculate the height of a wave?