Why do metals have a large number of free electrons?

Define work function of a metal. Give its unit.

What is photoelectric effect?

How does photocurrent vary with the intensity of the incident light?

Give the definition of intensity of light according to quantum concept and its unit.

How will you define threshold frequency?

What is a photo cell? Mention the different types of photocells.

State de Broglie hypothesis.

Why we do not see the wave properties of a baseball?

A proton and an electron have same kinetic energy. Which one has greater de Broglie wavelength. Justify.

Write the relationship of de Broglie wavelength λ associated with a particle of mass m in terms of its kinetic energy K.

Name an experiment that shows the wave nature of the electron. Which phenomenon was observed in this experiment using an electron beam?

An electron and an alpha particle have same kinetic energy. How are the de Broglie wavelengths associated with them related?

A deuteron and an alpha particle are accelerated with the same potential. Which one of the two has i) greater value of de Broglie wavelength associated with it and ii) less kinetic energy? Explain.