Question

Q. Why it is easier to skate on ice than on a smooth aluminium sheet ?
Q. State the principle of a thermometer.

Answer 1

Dear Student,

1- Coefficient of friction for ice surface is less as compare to aluminium surface so ice surface is more smooth than aluminium surface so slipping of body is more easy in ice surface.

2- Thermometer is based on the principle of volume expansion and contraction due rise and fall of temperature for liquids and solids. So with rise in temperature mercury will rise and with fall of temperature level of mercury will fall in mercury thermometer.

Regards.