Question

A certain freezing process requires that room temperature be lowered from 460C at the rate
of 20C every hour.
i) What will be the room temperature 10 hours after the process begin?
ii) How many hours will it take for the room temperature to be at 60C?

Answer 1

Step-by-step explanation:

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Question 70

Q6) A certain freezing process requires that room temperature be lowered from 40°C at the rate of 5°C every hour. What will be the room temperature 10 hours after the process begins?

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Solution 6:

The present room temperature = 40\degree C

The room temperature decreasing every hour by rate of = 5\degree C

The room temperature after 10 hours will be

= 40\degree C\ +\ 10\times\left(-5\degree C\right)

= 40\degree C-50\degree C\

= -10\degree C

so, the room temperature after 10 hour = -10\degree C

Answer 2

Answer:

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Step-by-step explanation:

Given that

Let us assume that the lowered temperature as negative,

Initial temperature = 40oC

Change in temperature per hour = -5oC

Change in temperature after 10 hours = (-5) × 10 = -50oC

∴The final room temperature after 10 hours of freezing process = 40oC + (-50oC)

= -10oC

The room temperature 10 hours after the process begins= -10oC