Warning: foreach() argument must be of type array|object, bool given in /var/www/html/web/app/themes/studypress-core-theme/template-parts/header/mobile-offcanvas.php on line 20

.. CP In the circuit in Fig. E26.19, a 20.0Ωresistor is inside 100gof pure water that is surrounded by insulating styrofoam.

If the water is initially at, how long will it take for its temperature to rise to58°C?

Short Answer

Expert verified

time required is t = 1006 s

Step by step solution

01

Step 1:About resitance in parrallel

theequivalentresistorofthecircuit
For the three branches in the circuit, each branch has two resistors in series; 80, the equivalent resistor of each branch is the
sum of the two resistors as shown by step (1) in the ?gure below.
Now, we have three resistors in parallel; Using equation 262, the equivalent resistor is given as followg
1Req=120+120+110

=15Ω

Req,1=5Ω

have three resistors in series, thus the equivalent resistor of the circuit is
Req=20+5+5=30Ω
Using Ohm‘s law, the current of the circuit is;
l=VReq=30V30Ω=1A

Sincetheresistor20Qisinseries,thesamecurrentis?owingthroughit.
From equation (25.18), the pOWer dissipated in a resistor R with current I flowing through is given by:
P=I2R
Now, we plug our values for R20 Q and I, so We get the pOWer dissipated in the resistor 20 Q:

r 20 Q:

P=12×20=20J/s
This is the rate of energy change from electic energy to thermal energy

02

Determine the time required

“’0know.fromequation17.13,theenergyrequiredtocauseatemperature
change AT of a substance of speci?c heat. I: and mass m is given by:
E=mcT
“’0 know, from equation 17.131 the energy required to cause a temperature
change AT of a substance of speci?c heat. c and mass m is given by:

For the water surrounding the resistor ‘20 52, we have

m=0.100kg,c=4190J/kg,T=48
’I‘lms, the energy e’lsferred from the registor 1.0 the water isF=20112J
Now, we lmve Llu‘e power and the total energy required L0 raise the temperature
of the water, the time rm‘luired for this process is:
t=EP=2011220=1005.6s

therefore time required is t = 1006 s

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

A typical small flashlight contains two batteries, each having an emf of1.5V, connected in series with a bulb having resistance17Ω. (a) If the internal resistance of the batteries is negligible, what power is delivered to the bulb? (b) If the batteries last for1.5hwhat is the total energy delivered to the bulb? (c) The resistance of real batteries increases as they run down. If the initial internal resistance is negligible, what is the combined internal resistance of both batteries when the power to the bulb has decreased to half its initial value? (Assume that the resistance of the bulb is constant. Actually, it will change somewhat when the current through the filament changes, because this changes the temperature of the filament and hence the resistivity of the filament wire.)

The current in a wire varies with time according to the relationship

I=55A-(0.65As2)t2. (a) How many coulombs of charge pass a cross section of the wire in

the time interval between t=0and role="math" localid="1655721302619" t=8.0s? (b) What constant current would transport the

same charge in the same time interval?

An open plastic soda bottle with an opening diameter of 2.5cmis placed on a table. A uniform 1.75-Tmagnetic field directed upward and oriented25° from the vertical encompasses the bottle. What is the total magnetic flux through the plastic of the soda bottle?

The power rating of a light bulb (such as a 100-W bulb) is the power it dissipates when connected across a 120-V potential difference. What is the resistance of (a) a 100-W bulb and (b) a 60-W bulb? (c) How much current does each bulb draw in normal use?

Two coils are wound around the same cylindrical form. When the current in the first coil is decreasing at a rate of , the induced emf in the second coil has magnitude 1.65×10-3V. (a) What is the mutual inductance of the pair of coils? (b) If the second coil has 25 turns, what is the flux through each turn when the current in the first coil equals 1.20A? (c) If the current in the second coil increases at a rate of 0.360A/s, what is the magnitude of the induced emf in the first coil?

See all solutions

Recommended explanations on Physics Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free