Answer:
You are exactly right. The molecules in hot air are moving faster than the molecules in cold air. Because of this, the molecules in hot air tend to be further apart on average, giving hot air a lower density. That means, for the same volume of air, hot air has fewer molecules and so it weighs less
Answer:
Faraday invented the electromagnetic rotation.
Explanation:
Faraday invented a device called electromagnetic rotation, Faraday got a rotation with magnetic force, he used a cable, mercury, and a magnet.
The cable would rotate around the magnet, this would be a beginning for the electromagnetic technology.
For example:
The Homopolar motor or called electric motor was created for Faraday's invention.
We can find electric motor in Washing machines, fans, turbines, even in motorcycles and electric cars.
Any of the above depending on the direction of forces
