Home
Class 11
PHYSICS
Temperature of a steel block changes fro...

Temperature of a steel block changes from `80^(@)C` to `75^(@)C` in time `t_(1)`, from `75^(@)C` to `70^(@)C` in time `t_(2)` and from `70^(@)C` to `65^(@)C` in time `t_(3)` then . . . . . . . . .

A

`t_(1)=t_(2)=t_(3)`

B

`t_(1)ltt_(2)=t_(3)`

C

`t_(1)ltt_(2)ltt_(3)`

D

`t_(1)gtt_(2)gtt_(3)`

Text Solution

Verified by Experts

The correct Answer is:
C
According to Newton.s law of cooling,
`(dQ)/(dt)` is proportional to the temperature differnce. It decreases as temperature decreases. So at high temperature, time is less for `5^(@)C` decrease in temperature and at lower temperature, time is more for `5^(@)C` decrease in temperature.
`:.t_(1)lt t_(2) lt t_(3)`
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • THERMAL PROPERTIES OF MATTER

    KUMAR PRAKASHAN|Exercise Section - F Question from Module (Sample questions for preparation of competitive exams)|18 Videos

  • THERMAL PROPERTIES OF MATTER

    KUMAR PRAKASHAN|Exercise Question Paper (Section - A) Answer following in one sentence : (Word limit of answer is 10) (Each question carries 1 mark)|6 Videos

  • THERMAL PROPERTIES OF MATTER

    KUMAR PRAKASHAN|Exercise Section - D NCERT Exemplar Solution (Long Answer Type Questions )|8 Videos

  • SYSTEMS OF PARTICLES AND ROTATIONAL MOTION

    KUMAR PRAKASHAN|Exercise SECTION-F (SECTION-D) QUESTIONS PAPER|1 Videos

  • THERMODYANMICS

    KUMAR PRAKASHAN|Exercise Question Paper|11 Videos

Similar Questions

Explore conceptually related problems

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

A body cools from 80^(@)C to 50^(@)C in 5 minutes Calculate the time it takes to cool from 60^(@)C to 30^(@)C . The temperature of the surroundings is 20^(@)C .

Knowledge Check

  • A hot liquid in beaker at 80^(@)C cools down to 70^(@)C in 2 minutes in an atmosphere of 30^(@)C temperature, then time taken to cool it down from 60^(@)C to 50^(@)C is . . . . . . ..

    A
    240
    B
    360
    C
    480
    D
    216

  • The temperature of O_(2) gas is changed from 25^(@)C to 50^(@)C then change in volume is ………….. (definite quantity of gas and constant pressure).

    A
    less than twice
    B
    more than twice
    C
    Half
    D
    Twice

  • Certain quantity of water cools from 70^(@)C to 60^(@)C in the first 5 minutes and to 54^(@)C in the next 5 minutes and to 54^(@)C in the next 5 minutes. The temperature of the surroundings is

    A
    `45^(@)C`
    B
    `20^(@)C`
    C
    `42^(@)C`
    D
    `10^(@)c`

    • Similar Questions

    Explore conceptually related problems

    A pan filled with hot food cools from 94^(@)C to 86^(@)C in 2 minutes when th room temperature is at 20^(@)C . How long will it take to cook from 71^(@)C to 69^(@)C ?

    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 80 ^(@) C " to " 50 ^(@) C in 5 minutes. Calculate the time it takes to cool from 60 ^(@) C " to " 30^(@) C . The temperature of the surroundings is 20 ^(@) C .

    The temperature of two bodies measured by a thermometer are t_(1) = 20^(@)C pm 0.5^(@)C and t_(2)=50^(@)C pm 0.5^(@)C . Calculate the temperature difference and the error theirin.

    A pan filled with hot food cools from 94^(@) C " to " 86^(@) C in 2 minutes when the room temperature is at 20^(@) C . How long will it take to cool from 71^(@) C " to " 69^(@) C ?

    Home
    Profile