Question

Explain why the current that makes the heater element very hot only slightly warms the connecting wires leading to the heater

Answer 1

this is because heating element of heater is comparatively high in terms of resistance with the copper wire

Answer 2

The wires are made of nichrome which have high specific resistance /resistivity is high AND is resistance increase to a great extent WITH increase in temperature but nichrome wires have high melting point thus the wire doesn't become very hot.
hope it helps u buddy
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