Check all the CORRECT statements about light:

• Light is considered a mechanical wave.

• Light is considered an electromagnetic wave.

• Light behaves like a wave only.

• Light behaves like a wave and a particle of energy.

Which one is the correct equation of the speed of light?

• C= λ x f

• C= λ/f

• C= λ + f

Based on the picture of the electromagnetic spectrum, Which one has higher Energy: X-Ray or Microwaves? And which one has higher wavelength: UV or Infrared?

True or False: Electromagnetic waves can travel through space (Vaccum)

• True

• False

If a beam of light has a wavelength (λ) of  $6\times10^{-7}\ m$   . find its frequency (f). Hind speed of light (c) =  $3.0\times10^8\ \frac{m}{s}$   

•  $5\ \times10^{14}\ Hz$  

•  $5\ \times10^{12}\ Hz$  

•  $5\ \times10^{10}\ Hz$  

Sound is an example of a mechanical wave because it needs a _____________ to travel through.

A continuous spectrum contains all the wavelengths of visible light?

• True

• False

Which statements are correct about the atomic (line) spectrum of hydrogen? see the attached image for reference

• Hydrogen can emit light at wavelength of 500 nm

• The visible light section of atomic spectrum of hydrogen contains only 4 lines

• The atomic spectrum of hydrogen is unique. meaning no element has a similar spectrum

• We can get the atomic spectrum of hydrogen by heating it through electrical discharging.

Metals can eject or release electrons when they are hit by a beam of energy (Light of certain frequency). This effect is called:

• Photoelectric effect

• Geomechanic effect

• Electromagnetic effect