OCR A-Level Physics A H556
Practical Skills in the Written Papers
The Practical Endorsement
Physical Quantities and Units
Making Measurements and Analysing Data
Nature of Quantities
Motion
Forces in Action
Work, Energy and Power
Materials
Newton’s Laws of Motion and Momentum
Charge and Current
Energy, Power and Resistance
Electrical Circuits
Waves
Quantum Physics
Thermal Physics
Oscillations
Gravitational Fields
Astrophysics and Cosmology
Capacitors
Electric Fields
Electromagnetism
Nuclear and Particle Physics
Nuclear and Particle Physics
Exponential decay and radioactive dating
- 2 things to know
- Papers 1, 2 and 3
Overview
Recall questions on the exponential decay equations for activity and undecayed nuclei, modelling decay with dice and spreadsheets, and carbon dating and how the age of a sample is calculated.
What you need to know
Answer each one before you reveal it.
State the exponential decay equation for the number of undecayed nuclei N at time t.
Questions from this subtopic
Each one with the model answer underneath.
- 1
State the equation showing how activity varies with time.
Model answer
A = A₀e^(−λt)
- 2
In a dice simulation of radioactive decay, what does each die represent?
Model answer
An undecayed nucleus.
- 3
In the dice simulation, what action represents a nucleus decaying?
Model answer
Rolling a particular designated number, after which that die is removed.
- 4
What graph is plotted from the dice simulation results and what does it show?
Model answer
Number of remaining dice against number of throws, showing exponential decay.
- 5
Why is the dice rolling process repeated for multiple rounds?
Model answer
To demonstrate the random and exponential nature of radioactive decay over successive time intervals.
- 6
How is the new value of N calculated in each row of a radioactive decay spreadsheet model?
Model answer
By adding ΔN to the previous value of N.
Other ways to work this
The same content, four other ways.
What is inside Levo
Six ways to work the same material.
Every question in Nuclear and Particle Physics, on a schedule.
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