Compare the motion of the boy and the man who was going faster? Was their acceleration about the same? Who had more frictional force? What might have caused the difference in frictional force?

Which theory was contradicted by experiments with the photoelectric effect? light spreads out after it passes through a small opening. as soon as light strikes metal, electrons will be ejected. visible light, regardless of color, will cause the ejection of electrons when striking metal. the kinetic energy of ejected electrons depends on the frequency of light that strikes the metal.

What is the molecular weight of copper

One similarity and one difference between an element and a mixture of elements