Interactive practical

Estimating the Planck constant using LEDs

Measure LED current–voltage curves, estimate threshold voltages and use a voltage–frequency graph to estimate the Planck constant.

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Practice: Determining Planck's constant using LEDs

Eduqas A420QS — this practical matches your selected course; the questions check the method, data handling and practical skills.

Check your answers as you work. For written questions, use the marking points to assess your response.

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2 of 2 available questions match the selected filters. This session contains 2 questions.

Question 1 · 1 mark · Foundation · Practical · Diagnostic

Which relationship is used at the threshold p.d. of an LED?

Question 2 · 3 marks · Standard · Practical · Practical method

Estimating the Planck constant using LEDs

Practice: Determining Planck's constant using LEDs

Which relationship is used at the threshold p.d. of an LED?

Explain why a blue LED needs a higher threshold p.d. than a red LED.