Respuesta :
Answer:
t = 25s
Explanation:
The required temperature change is 50°C. (80 –30). The temperature of the bar increased 2°C in the first second. Assuming uniformity in the properties of the bar, in 2s the temperature would now be 2+2 = 4°C, in 3s it will be 2+2+2 =6°C.
So for gain a temperature change of 50°C, it will take 50/2 = 25s
ΔT /t = 2
t = ΔT/2 = 50/2 = 25seconds
Answer: It will take 43.2 seconds for the bar to reach 80 °C
Explanation: Please see the attachments below
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