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Printable Physics practice

Six original questions. Worked answers start on a separate page.

· Forces, energy and momentum PDF · DC circuits and electrical energy PDF · Waves, phase and interference PDF · GCSE density and measurement PDF · GCSE heating and changes of state PDF · GCSE Hooke’s law and elastic energy PDF · GCSE practical calculations: mixed review PDF

Each set number reproduces the same questions. For classroom display or interactive checking, open a question’s practice link.

Treat the given values as exact unless an uncertainty is stated.

Waves, phase and interference

Set 42 · Original PhysicsHelp questions · Selected AQA 7408 / OCR A H556 skills

Question 1

A progressive wave travels at 300 m s⁻¹ with frequency 500 Hz. Find its wavelength. Give your answer to 3 significant figures.

waves-interference / wavelength / v1.0.0 / seed 42 · Check interactively

Question 2

A wave has period 6 ms. Find its frequency. Give your answer to 3 significant figures.

waves-interference / frequency / v1.0.0 / seed 104771 · Check interactively

Question 3

Two points on the same progressive wave are 0.6 m apart along its direction of travel. Wavelength is 0.8 m. Calculate their phase separation as a positive angle from 0° to 360°, using 360° for one wavelength. Keep angles above 180° in this convention. Give your answer to 3 significant figures.

One cycle = λ
Schematic snapshot of a progressive transverse wave. One complete spatial cycle is one wavelength.

waves-interference / phase / v1.0.0 / seed 209500 · Check interactively

Question 4

In Young’s double-slit experiment, wavelength is 550 nm, slit separation is 0.5 mm and screen distance is 1.2 m. Find adjacent bright-fringe spacing in mm. Use the small-angle approximation. Give your answer to 3 significant figures.

waves-interference / fringe-spacing / v1.0.0 / seed 314229 · Check interactively

Question 5

Adjacent nodes of a stationary wave on a string are 0.14 m apart. Find the wavelength of the progressive waves forming it. Give your answer to 3 significant figures.

waves-interference / node-separation / v1.0.0 / seed 418958 · Check interactively

Question 6

A string of length 1.2 m is fixed at both ends. Wave speed is 250 m s⁻¹. Find the frequency of harmonic 3. Ignore changes in tension and end effects. Give your answer to 3 significant figures.

3 half-wavelengths in length L
Possible shape at maximum displacement for harmonic 3 on a string fixed at both ends. The marked nodes have zero displacement.

waves-interference / string-harmonic / v1.0.0 / seed 523687 · Check interactively

Worked answers — Waves, phase and interference

Set 42. Keep intermediate values unrounded. The stated practice checks accept values rounding to 3 significant figures.

Question 1

  1. λ = 300/500 m.
  2. Answer: 0.600 m (3 significant figures).

Question 2

  1. T = 6 × 10-3 s.
  2. f = 1/(6 × 10-3) Hz.
  3. Answer: 167 Hz (3 significant figures).

Question 3

  1. Phase difference = (0.6/0.8) × 360°.
  2. Answer: 270 ° (3 significant figures).

Question 4

  1. w = (550 × 10-9) × 1.2/(0.5 × 10-3) m.
  2. Multiply the spacing in m by 1000 to give mm.
  3. Answer: 1.32 mm (3 significant figures).

Question 5

  1. λ = 2 × 0.14 m.
  2. Answer: 0.280 m (3 significant figures).

Question 6

  1. λ = 2 × 1.2/3 m.
  2. f = 3 × 250/(2 × 1.2) Hz.
  3. Answer: 313 Hz (3 significant figures).