imagine a strongman at the circus. He picks up a bowling ball and spins it on the tip of his finger, as if it was a basketball. Then he sets down the bowling ball and picks up a barbell with weights on it, balances it on his finger the same way, and spins it like he did with the bowling ball. The barbell and bowling ball weigh the same, but he finds it much harder to start and stop the barbell. This is because the weights on the barbell are further from his finger, and so they act like a lever. The weight in the bowling ball is closer to the finger, so it acts like a lever too, but a shorter one, and a longer lever (like a pry bar) makes the dumbbell act stronger than the bowling ball.
IIRC Angular momentum is about the momentum of something attached to the end of a ‘lever’ or ‘pry bar’, so it acts stronger. Because the weight is attached, the weight can’t fly off, so the attachment (bar of barbell, for example) holds it in like a dog running in circles on a leash.
From this you could figure out why a wide flywheel wants to keep spinning at the same speed, where a narrower flywheel would be easier to speed up or slow down.
Latest Answers