Physics 0625 · IGCSE · Light

Light — practice question

Fig. 5.1 shows an object placed on the principal axis of a thin lens. Each small square in the grid stands for 0.5 cm. Each principal focus of the lens carries the label F.
(a)[1]

Use the grid to find the focal length of the lens.

(b(i))[1]

On Fig. 5.1, draw a ray from the top of the object that goes through a principal focus, then passes through the lens and beyond it.

(b(ii))[1]

On Fig. 5.1, draw a second ray from the top of the object that goes through the centre of the lens. Extend this ray to the edge of the grid.

(b(iii))[2]

On Fig. 5.1, draw an arrow to indicate the location and nature of the image formed by the lens.

Worked solution & mark scheme

This 5-mark question has a full step-by-step worked solution and mark scheme. One marking point: Focal length is 5 cm

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