A liquid cools from 65°C to 55°C in 5 mins. If the surrounding temperature is 35℃, calculate the time taken for temperature to fall from 45°C to 35°C.(a) 25sec(b) 25min(c) 30min(d) 30secI have been asked this question in semester exam.Origin of the question is Thermal Properties of Matter topic in division Thermal Properties of Matter of Physics – Class 11

A liquid cools from 65°C to 55°C in 5 mins. If the surrounding tempe

1.	A liquid cools from 65°C to 55°C in 5 mins. If the surrounding temperature is 35℃, calculate the time taken for temperature to fall from 45°C to 35°C.(a) 25sec(b) 25min(c) 30min(d) 30secI have been asked this question in semester exam.Origin of the question is Thermal Properties of Matter topic in division Thermal Properties of Matter of Physics – Class 11
Answer» The CORRECT answer is (b) 25min The explanation is: Average temperature of liquid in the first case = 60℃. Rate of FALL of temperature =65-55 / 5 = 2°C /min. Which is also equal to k(60 – 35) = 25k, where k is a constant. ∴ 25k = 2 Or k = 2/25 Average temperature in the second case = 40°C Rate of fall of temp = 45 – 35 / t = k(40-35) ∴ t = 25mins.

Discussion

No Comment Found

Related InterviewSolutions

At a given temperature a body emits energy of a single wavelength corresponding to that temperature. True or False?(a) True(b) FalseThe question was asked in quiz.This is a very interesting question from Thermal Properties of Matter in portion Thermal Properties of Matter of Physics – Class 11
Temperature is absolute. True or False?(a) True(b) FalseThis question was addressed to me in unit test.This interesting question is from Measurement of Temperature in portion Thermal Properties of Matter of Physics – Class 11
Quantitatively heat conduction can be described as?(a) Heat flow for a given temperature difference(b) Time rate of heat flow for a given temperature difference(c) Temperature difference caused due to heat flow per unit time(d) Temperature difference per unit quantity of heat transferredThis question was posed to me in examination.My question is taken from Thermal Properties of Matter in portion Thermal Properties of Matter of Physics – Class 11
When water is kept in a very hot pan, the entire water heats up. Which mode of heat transfer is responsible for this?(a) Conduction(b) Convection(c) Radiation(d) Convection along with radiationThe question was asked during an internship interview.The question is from Thermal Properties of Matter in chapter Thermal Properties of Matter of Physics – Class 11
What is regelation?(a) Refreezing of ice on addition of impurities(b) Refreezing of ice on reduction in pressure(c) Melting of ice at lower temperature than its melting point due to increase in pressure(d) Melting of ice at higher temperature than its melting pointThe question was posed to me by my school principal while I was bunking the class.I would like to ask this question from Thermal Properties of Matter topic in division Thermal Properties of Matter of Physics – Class 11
Melting point depends on pressure. True or False?(a) True(b) FalseThe question was posed to me at a job interview.My doubt stems from Thermal Properties of Matter topic in chapter Thermal Properties of Matter of Physics – Class 11
What should be the temperature of 1g of ice, so that when it’s added to 9g of water, lowers the temperature of water by 10°C?Sw = 1cal/ g°C, Sice = 0.5cal/ g°C, Lfus= 80cal/g.(a) 20°C(b) -20°C(c) 0°C(d) 10°CI got this question by my college professor while I was bunking the class.The above asked question is from Thermal Properties of Matter in chapter Thermal Properties of Matter of Physics – Class 11
What is the relation between coefficient of area expansion(A) and coefficient of volume expansion(B)?(a) B = 1.5A(b) A = 1.5B(c) A = 3B(d) B = 3AThis question was posed to me in quiz.My doubt is from Thermal Expansion topic in section Thermal Properties of Matter of Physics – Class 11
Two spheres, A & B, are made up of the same material. The radius of A is twice that of B, while the temperature of A is half that of B. What is their ratio of energy emitted per unit time (EA : EB)?(a) 1(b) 1/4(c) 1/2(d) 1/16The question was posed to me during an online interview.I would like to ask this question from Thermal Properties of Matter in division Thermal Properties of Matter of Physics – Class 11
Getting burnt by steam is less dangerous than boiling water. True or False?(a) True(b) FalseThe question was posed to me in an interview for job.Origin of the question is Thermal Properties of Matter in portion Thermal Properties of Matter of Physics – Class 11

Discussion

No Comment Found

Related InterviewSolutions

Reply to Comment