Lenses (physics only) knowledge questions for AQA GCSE Physics

How does a lens form an image?
For a convex lens where are parallel rays of light brought to a focus? Can you draw a diagram to show this?
What is the distance from the lens to the principal focus called?
Complete the following – The image produced by a convex lens can be either __________ or _______________. The image produced by a concave lens is always ______________.
Draw the symbols used to represent convex and concave lenses.
State the equation to calculate the magnification of an object.
What are the possible units for image height and object height?
Why does magnification have no units?
Watch the two videos below and make sure that you can construct all the ray diagrams. Thank you to the brilliant free science lessons YouTube Channel.