I think my physics teacher told me this fact but followed it up with “Measuring a planet’s rotation around the sun by how fast it rotates around it’s center is like trying to measure the speed of a truck based on how many rotations a ballerina can spin inside of it.”
Bit silly. In this scenario, you’re not measuring the speed of the truck. You’re measuring the time it takes to complete a lap. And we are the ballerina rotating, and as we are a miniature plastic ballerina with no outside frame of reference, our own regular rotation is the only consistent measure we have.
I think my physics teacher told me this fact but followed it up with “Measuring a planet’s rotation around the sun by how fast it rotates around it’s center is like trying to measure the speed of a truck based on how many rotations a ballerina can spin inside of it.”
That quote haunts me.
Bit silly. In this scenario, you’re not measuring the speed of the truck. You’re measuring the time it takes to complete a lap. And we are the ballerina rotating, and as we are a miniature plastic ballerina with no outside frame of reference, our own regular rotation is the only consistent measure we have.
How did the ballerina get inside the truck? Is she alright?!
Is she spinning because she’s happy? Or is she spinning to drill a hole in the floor and escape?