Q15 of 216 Page 456

AB is a current-carrying conductor in the plane of the paper as shown in the figure. What are the directions of magnetic fields produced by it at points P and Q? Given r1 > r2, where will the strength of the magnetic field be larger?

Direction of current can be calculated by right-hand thumb rule.


According to this rule, thumb denotes the direction of current and fingers are curled in the direction where the magnetic field needs to be find out.


By this magnetic field at P is inside the paper and at Q is outside. Magnet field at Q is larger than at P as the distance is inversely proportional to the magnetic field.


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OR


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(a) The strength of forces between constituent elements


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(a) Metal M which is in the middle of the reactivity series.


(b) Metal N which is high up in the reactivity series.


Given one example of each type.


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A salt X is formed, and gas is evolved when ethanoic acid reacts with sodium hydrogen carbonate.

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