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Miracle Learning Centre Physics Tuition Question on The D.C motor (O Level Science Tuition/IP Science Tuition/Secondary Science Tuition)

1) The figure shows a cross-sectional view of a simple d.c. motor. The circles represent the sides of a rectangular coil which is placed between the poles of a permanent magnet. The current in the right-hand side of the coil flows into the diagram; the current in the left-hand side of the coil flows out of the plane of the diagram.

a Draw lines to indicate the direction of the force experienced by each side of the coil. [2] b Explain how the forces you have shown in a make the coil rotate. [2] ………………………………………………………………………………………….. ………………………………………………………………………………………….. ………………………………………………………………………………………….. c State two ways in which the turning effect experienced by the coil could be increased. In each case, explain why the turning effect is increased. [4] ………………………………………………………………………………………….. ………………………………………………………………………………………….. ………………………………………………………………………………………….. ………………………………………………………………………………………….. ………………………………………………………………………………………….. ………………………………………………………………………………………….. d State two ways in which a practical motor will be different from the simple motor drawn in the figure above. [2] ………………………………………………………………………………………….. ………………………………………………………………………………………….. ………………………………………………………………………………………….. ………………………………………………………………………………………….. …………………………………………………………………………………………..

Miracle Learning Centre Answer to Science Tuition Question on The D.C motor. (O Level Science Tuition/IP Science Tuition/Secondary Science Tuition)

The figure shows a cross-sectional view of a simple d.c. motor. The circles represent the sides of a rectangular coil which is placed between the poles of a permanent magnet. The current in the right-hand side of the coil flows into the diagram; the current in the left-hand side of the coil flows out of the plane of the diagram.

Draw lines to indicate the direction of the force experienced by each side of the coil. [2] 1 mark each for correct direction of arrow (ii) Explain how the forces you have shown in i make the coil rotate. [2]

(iii) State two ways in which the turning effect experienced by the coil could be increased. In each case, explain why the turning effect is increased. [4]

(iv) State two ways in which a practical motor will be different from the simple motor drawn in the figure above. [2]