The Electromagnetic Spectrum

4 marks · Normal

A teacher shines visible red light (wavelength m) and uses a microwave oven that emits microwaves of wavelength m.

(a)

Calculate the frequency of the red light. Take the speed of light in a vacuum as m/s.

[2 marks]

(b)

Calculate the frequency of the microwave.

[2 marks]

Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.

Show answer

(a) Hz

(b) Hz

Common mistakes: mixing up f = c/λ

Show mark scheme and worked solution

Marking points

M1 (a) · 1 mark · Correct substitution into speed equation and rearrangement. (follow-through)

A1 (a) · 1 mark · Correct evaluation for red light ( Hz). Allow rounding. (follow-through)

M2 (b) · 1 mark · Correct substitution into for microwave. (follow-through)

A2 (b) · 1 mark · Correct evaluation for microwave ( Hz). Allow rounding. (follow-through)

Worked solution

(a) Red light: Hz

(b) Microwave: Hz