Home
Class 11
PHYSICS
A piece of hot copper at 100^(@)C is plu...

A piece of hot copper at `100^(@)`C is plunged into a pond at `30^(@)`C. The copper cools down to `30^(@)`C, while the pond, being huge, stays at its initial temperature. Then-

A

Copper loses some entropy, the pond stays at the same entropy

B

Copper loses some entropy, and the pond gains exactly the same amount of entropy

C

Copper loses entropy and the pond gains more than this amount of entropy

D

Both copper and the pond gain in entropy

Text Solution

Verified by Experts

The correct Answer is:
C

Using theory of entropy it is evident that answer is (c).
Promotional Banner

Similar Questions

Explore conceptually related problems

A 5 g piece of ice at — 20^° C is put into 10 g of water at 30^° C. The final temperature of mixture is

A body initially at 80^(@)C cools to 64^(@)C in 5 minutes and to 52^(@)C in 10 minutes. What is the temperature of the surroundings?

A body at 50^(@)C cools in a surroundings maintained at 30^(@)C The temperature at which the rate of cooling is half that of the beginning is .

An object at temperature 70^(@)C is placed in a surrounding medium of temperature 30^(@)C . Its temperature decreases by 10^(@)C in first 5 min. Find the time interval from starting in which its temperature reduces to 40^(@)C . Assume Newton's law to be valid. t = 0 " "T = 70^(@)C" "T_("env") = 30^(@)C t = 5 " "T = 60^(@)C" "T_("env") = 30^(@)C time = t T = 40^(@)" " T_("env") = 30^(@)C

Water of mass 200 g and temperature 30^(@)C is taken in a copper calorimeter of mass 50g and temperature 30^(@)C . A copper sphere of mass 100g and temperature 100^(@)C is released into it. What will be the maximum temperature of the mixture ? [ c ( water = 1 cal //g.^(@) C , c ( copper ) = 0.1 cal//g.^(@)C ]

A copper calorimeter, blackened outside, is filled with some hot liquid and placed on a table. It is found to cool from 60^(@)C to 50^(@)C in 4 minutes and 40^(@)C to 30^(@)C in 8 minutes. What is the temperature of the surroundings? Why is blackened?

A liquid initially contracts when cooled down to 4^(@)C but on further cooling down to 0^(@)C , it expands. The liquid is :

A cup of tea cools from 80^(@)C to 60^(@)C in one minute. The ambient temperature is 30^(@)C . In cooling from 60^(@)C to 50^(@)C it will take

If a liquid takes 30 seconds in cooling of 80^(@)C to 70^(@)C and 70 seconds in cooling 60^(@)C to 50^(@)C , then find the room temperature.

A body cools from 60^(@)C to 50^(@)C in 10 minutes when kept in air at 30^(@)C . In the next 10 minut es its temperature will be