Asmall metal bar, whose initial temperature was 20°c, is dropped into a large container of boiling water. how long will it take the bar to reach 90°c if it is known that its temperature increases 2°in 1 second? how long will it take the bar to reach 98°c?

a) 35 s

b) 39 s

Explanation:

Initial temperature  T₁= 20 °C

Final temperature T₂= 90 °C

Temperature rise rate = 2 °C/s

To solve the problem we can use the formula T₁ + t * 2°C/s = T₂

Where t is the time, in seconds.

We solve for t :

20°C + t * 2°C/s = 90°C

t * 2°C/s = 70°C

t  = 35 s

20°C + t * 2°C/s = 98°C

t * 2°C/s = 78°C

t  = 39 s

distance, luminosity, brightness, radius, chemical composition, and temperature

the awnser is group 12