Question
State whether an electric heater will consume more electrical energy or less electrical energy per second when the length of its heating element is reduced. Give reasons for your answer.
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Answer
By reducing the length of element the resistance will decrease. Power is inversely proportional to resistance. So, this will result in more consumption of energy.
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ii. Name the part of the human brain which contains a vital centre for controlling blood pressure.
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| A | No reaction | Displacement | No reaction | Displacement | No reaction | No reaction |
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| D | No reaction | No reaction | No reaction | No reaction | No reaction | No reaction |
| E | Displacement | Displacement | Displacement | Displacement | No reaction | No reaction |
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2. To which group of periodic table does this non-metal belong?