Spinning Pencil
08:00 - 10:19
2m 19s
Phil conducts an experiment in which he tries to spin a pencil on its tip. He fails initially but is successful after sticking it through a circle of cardboard. He explains why it works and mentions the "smart" way to describe the phenomenom: the conservation of angular momentum.


Please sign in to write a comment.
Video Transcript

Related Clips

Phil conducts an experiment in which he makes a chain fly into the air due to the force of gravity. He explains how the experiment works and demonstrates it at a larger scale.
Phil demonstrates the use of mechanical advantage to pull heavy objects with less effort. He acts as a superhero named Mechanical Advantage Using a Force Man to move a car using a rope, mechanical advantage, and his own strength.
Buster Beaker explains how high and low tides are affected by the gravity of the moon and the sun. He illustrates the phenomenon using a cookie, a mushroom, and a lemon.
Phil explains and illustrates Newton's first law of motion and angular momentum using a 20 kg weight. In the experiment, they are having trouble spinning the weight fast enough. They eventually spin it fast enough that it doesn't topple over immediately.
Through a cartoon movie, Beakman explains why your stomach feels weird on a roller coaster and why the biggest hill is the first one. He hangs a bowling ball from the ceiling with a cable and then swings the ball to squish a watermelon (energy in and energy out). He then puts himself where the watermelon was and shows that the ball can't swing any farther than the point at which he lets go. Beakman goes on to explain that centripetal force prevents us from falling out of the roller coaster and demonstrates it. He uses a tray containing a glass of milk and a cupcake and quickly spins it around to show that nothing falls off. He then explains why inertia keeps us from falling to the ground and brings all of the concepts together.