Diminished means smaller than an object’s real size. It is the opposite of magnified.

A convex shape bulges ‘out’ rather than bulging ‘in’ (concave).

Rays of light incident on a convex lens parallel to the principal axis are focused to a point called the principal focus.

The focal length is the distance from the centre of the lens to the principal focus.

The greater the power of a lens, the greater the angles through which light is refracted and the shorter the focal length.

Convex lenses (including magnification)

Physics

Reflection of light (including specular and diffuse)

Refraction through a rectangular block (including wave front diagrams)

Refraction through a semicircular block

Light and colour

Scale diagrams for convex lenses (including magnification)

Virtual images from convex and concave lenses (including magnification)

The spectrum of electromagnetic radiation

Absorbing infrared radiation practical

Emitters of infrared & black body radiation

Ionising electromagnetic radiation

Non-ionising electromagnetic radiations

In A-level physics, some pupils will build on this knowledge to learn about the photon model of electromagnetic radiation and the use of electromagnetic radiation for collecting evidence about the universe or for generating images of the inside of a human body.

In the Measuring waves unit, pupils learnt about the measurable features of a wave, the relationship between them and the wave equation.

This unit explores reflection, refraction, and lenses using ray diagrams. It covers the electromagnetic spectrum, light as a wave, absorption, transmission, and practical uses. Emphasis is on risks, temperature balance, data presentation, and unit conversions.

Electromagnetic waves

Physical activity and equipment requiring safe use

Images of an object that are smaller than the object's actual size are described as {{}} images.

What is the name of the point labelled X in the diagram shown?

A bulb filament has a height of 0.5 cm. A convex lens produces an image of the bulb filament on a screen that has a height of 3.5 cm. 
Calculate the magnification of the filament by the lens.  

Which of the following could be correct reasons why this lens cannot currently produce an image of this object?

Image located between f and 2f, and is diminished.

 Image located further away than 2f, and is magnified.

No image forms as rays leaving the lens are parallel.

No image forms as rays leaving the lens are diverging.

Match each object distance with the correct characteristics of the image.
(f = focal length of the lens)

The lens makes all of the rays meet at a single point.

All the rays from a single point on the object meet at a single point.

The image will appear at the focal length of the lens.

At this object distance, an image of the tree cannot be formed on a screen.

The diagram shows many rays of light travelling from 4 points on an object passing through a lens. 
Given that object distance > focal length, which of the following statements are correct?

When a wave crosses a boundary and changes direction, this is called {{}}.

Which diagram shows the ray moving from air into glass and bending in the correct direction?

Which diagram shows the ray moving from glass into air and bending in the correct direction?

Its length equals the wavelength of the wave.

It passes through the point where the ray hits the boundary.

In a ray diagram, a normal line is often drawn. 
Which of the following statements about the normal are correct?

Light coming from a point on the apple always travels in a single direction.

Light travelling from the apple in one direction all comes from one point.

Which of the following statements about the apple shown is correct?

Which of the following ray diagrams is correct?

Starter Quiz

When a wave crosses a boundary and changes direction, this is called .