How much heat is needed to warm 0.052 kg of gold from 30 C to 120 C?

Why do electron microscopes have higher resolving power than light microscopes?

Suppose a wheel with a tire mounted on it is rotating at the constant rate of 2.15 times a second. a tack is stuck in the tire at a distance of 0.373 m from the rotation axis. noting that for every rotation the tack travels one circumference (a) find the tack's tangential speed. (b) what is the tacks radial acceleration?

Dao makes a table to identify the variables used in the equations for centripetal acceleration. what quantities belong in cells x and y?