A centigrade and a Fahrenheit thermometer are dipped in boiling water. The water temperature is lowered until the Fahrenheit thermometer registered at 140°F. What is the fall in temperature as registered by the centigrade thermometer ?

A centigrade and a Fahrenheit thermometer are dipped in boiling water.

1.	A centigrade and a Fahrenheit thermometer are dipped in boiling water. The water temperature is lowered until the Fahrenheit thermometer registered at 140°F. What is the fall in temperature as registered by the centigrade thermometer ?
Answer» `80^(@)` `60^(@)` `40^(@)` `30^(@)` Solution :`(DeltaC)/(5)=(DeltaF)/(9)rArr DeltaC =(5)/(9)DeltaF=(5)/(9)DeltaF=(5)/(9)(212-140)rArr DeltaC=40^(@)C`