# Physics - Uncertainty

# Uncertainty

What are the two types of uncertainty?

- Absolute uncertainty
- Percentage uncertainty

What is absolute uncertainty?

- A number that gives the range of values for an experiment.
- E.g. $7.3mm \pm 0.2mm$

What is percentage uncertainty equal to for a single measurement?

The resolution of the equipment.

What is percentage uncertainty equal to for multiple measurements?

The range of values divided by two.

What is the percentage uncertainty for $0.65mm, 0.58mm, 0.62mm$?

$\pm 0.3mm$

How do you calculate percentage uncertainty?

How does multiplication by a constant affect percentage uncertainties?

They are left the same.

How does multiplication by a constant affect absolute uncertainties?

They are multiplied by the constant.

How does addition or subtraction of quantities affect absolute uncertainties?

The uncertainties are added together.

How does multiplication or division of quantities affect percentage uncertainties?

The uncertainties are added together.

How does raising a value to a power affect percentage uncertainties?

The percentage uncertainty is multiplied by the power.

How do you deal with absolute uncertainties after using an operation like $\sin(x)$ or $\ln(x)$?

- Calculate the difference between the two min and max values after being put into the operation.