Draw a labelled diagram of an astronomical telescope and explain its working .Give an expressin for its magnifying power.

Draw a labelled diagram of a neuron.

Draw a labelled diagram of sperm.

Draw a labelled diagram of sperm.

Draw a labelled ray diagram of a compound microscope. Explain its working and derive an expression for its magnification power when final image is formed at a least distance of distinct vision.

Draw a labelled diagram of a d.c. motor. State its principle and explain its working.