Flag Thermal Physics> Water at 50°C is filled in a closed cylin...
question mark

Water at 50°C is filled in a closed cylindrical vessel of height 10 cm and cross-sectional area 10 cm2. The walls of the vessel are adiabatic but the flat parts are made of 1 mm thick aluminum (K = 200 J/m-s-°C). Assume that the outside temperature is 20°C. The density of water is 1000 kg/m°3, and the specific heat capacity of water = 4200 J/kg-°C. Estimate the time taken for the temperature to fall by 1.0°C. Make any simplifying assumptions you need but specify them.

Simran Bhatia , 10 Years ago
Grade 11
anser 1 Answers
Aditi Chauhan

Last Activity: 10 Years ago

Sol. A = 10cm^2, h = 10 cm ∆Q/∆t = KA(θ base 1 - θ base 2)ℓ = 200 * 10^-3 * 30/1 * 10^-3 = 6000 Since heat goes out form both surfaces. Hence net heat coming out. = ∆Q/∆t = 6000 * 2 = 12000, ∆Q/∆t = MS ∆θ/∆t ⇒ 6000 * 2 * 10^-3 * 10^-1 * 1000 * 4200 * ∆θ/∆t ⇒ ∆θ/∆t = 72000/420 = 28.57 So, in 1 Sec. 28.57°C is dropped Hence for drop 1°C 1/28.57 sec. = 0.0035 sec. is required

Provide a better Answer & Earn Cool Goodies

star
LIVE ONLINE CLASSES

Prepraring for the competition made easy just by live online class.

tv

Full Live Access

material

Study Material

removal

Live Doubts Solving

assignment

Daily Class Assignments


Ask a Doubt

Get your questions answered by the expert for free