All Matches

Solution Library

Expert Answer

Textbooks

Search Textbook questions, tutors and Books

Oops, something went wrong!

Change your search query and then try again

Result Not Found

Books FREE
Tutors
Study Help
Ask a Question

Search
Sign In
Register

study help
physics
electricity and magnetism

Questions and Answers of Electricity and Magnetism

If the resistance of a small immersion heater (to heat water for tea or soup, Fig.18-32) was increased, would it speed up or slow down the heating process? Explain.
With two identical light bulbs and two identical batteries, how would you arrange the bulbs and batteries in a circuit to get the maximum possible total power out? (Assume the batteries have
If a rectangular solid made of carbon has sides of lengths a, 2a, and 3a, how would you connect the wires from a batter so as to obtain?(a) The least resistance,(b) The greatest resistance?
If two identical resistance are connected in series to a battery, does the battery have to supply more power or less power than when only one of the resistance is connected? Explain.
The equation P = V2/R indicates that the power dissipated in a resistor decreases if the resistance is increased, whereas the equation P – P R implies the opposite. Is there a contradiction there?
You have a single 60-W bulb on in you room. How does the overall resistance of your room’s electric circuit change when you turn on an additional 100-W bulb?
When applying Kirchhoff€™s loop rule (such as in Fig. 19-35), does the sign (or direction) of a battery€™s emf depend on the terminal voltage?
What happens when a lightbulb burns out?
Explain why lightbulbs almost always burn out just as they are turned on and not after they have been on for some time?
Which draws more current, a 100-W lightbulb or a 75-W bulb? Which has the higher resistance?
Given the circuit shown in Fig. 19-36, use the words €˜€™increase,€™€™ €˜€™decrease,€™€™ or€™€™
Electric power is transferred over large distances at very high voltages Explain how the high voltage reduces power losses in the transmission lines.
For what use are batteries connected in series? For what use are they connected in parallel? Does it matter if the batteries are nearly identical or not in either case?
A 15-A fuse blows repeatedly. Why is it dangerous to replace this fuse with a 25-A fuse?
When electric lights are operated on low-frequency ac (say. 5 Hz), they flicker noticeably why?
Driven by ac power, the same electrons pass back and forth through your reading lamp over and over again. Explain why the light stays lit instead of going out after the first pass of electrons.
Can the terminal voltage of a battery ever exceed its emf? Explain.
The heating element in a toaster is made of Nichrome wire. Immediately after the toaster is turned on, is the current (l rms) in the wire increasing, decreasing, or staying constant? Explain.
Explain in detail how you could measure the internal resistance of a battery.
Is current used up in a resistor? Explain.
Different lamps might have batteries connected in either of the two arrangements shown in Fig. 18-33. What would be the advantages of each scheme?
Compare and discuss the formulas for resistance and for capacitor when connected in series and in parallel.
A current of 1.30A flows in a wire. How many electrons are flowing past any point in the wire per second?
A service station charges a battery using a current of 6.7 A for 5.0h. How much charge passes through the battery?
What is the current in amperes if 1200 Na + ions flow across a cell membrane is 3.5 μs? The charge on the sodium is the same as on an electron, but positive.
What is the resistance of toaster if 120V produces a current of 4.2A?
What voltage will produce 0.25 A of current through a 3800-Ω resistor?
A hair dryer draws 7.5A when plugged into a 120-V line.(a) What is its resistance?(b) How much charge passes through it in 15 min? (Assume direct current.)
An electric clothes dryer has a heating element with a resistance of 9.6 Ω. (a) What is the current in the element when it is connected to 240V? (b) How much charge passes through the element
A 9.0-V battery is connected to a bulb whose resistance is 1.6Ω. How many electrons leave the battery per minute?
A bird stands on a dc electric transmission line carrying 2800 A (Fig. 18-34). The line has 2.5 X 10-5 Ω resistance per meter, and the bird€™s feet are 4.0 cm apart. What is the
An electric device draws 6.50 A at 240 V. (a) If the voltage drops by 15%, what will be the current, assuming nothing else changes?(b) If the resistance of the device were reduced by 15%, what
A 12-V battery causes a current of 0.60 A through a resistor.(a) What is its resistance, and (b) How many joules of energy does the battery lose in a minute?
What is the diameter of a 1.00-m length of tungsten wire whose resistance is 0.32Ω?
What is the resistance of a 3.5-m length of copper wire 1.5 mm in diameter?
Calculate the ratio of the resistance of 10.0m of aluminum wire 2.0 mm in diameter, to 20.0m of copper wire 2.5 mm in diameter.
Can a 2.5-mm-diameter copper wire have the same resistance as a tungsten wire of the same length? Give numerical details.
A certain copper wire has a resistance of 10.0Ω. At what point along its length must the wire be cut so that the resistance of one piece is 4.0 times the resistance of the other? What is the
How much would you have to raise the temperature of a copper wire (originally at 20oC) to increase its resistance by 15%?
Estimate at what temperature copper will have the same resistivity as tungsten does at 20oC.
Suppose that three identical capacitor are connected to a battery. Will they store energy if connected in series or in parallel?
Why is it more dangerous to turn on an electric appliance when you are standing outside in bare feet than when you are inside wearing shoes with thick soles?
A 100-W lightbulb has a resistance of about 12Ω when cold (20oC) and 140Ω when on (hot). Estimate the temperature of the filament when hot assuming an average temperature coefficient of
Figure 19-37 is a diameter of a capacitor (or condenser) microscope. The changing air pressure in a sound wave causes one plate of a capacitor C to move back and forth. Explain how a current of the
Compute the voltage drop along a 26-m length of household no. 14 copper wire (used in 15-A circuits). The wire has diameter 1.628 mm and carries a 12-A current.
Design a circuit in which two difference switches of the type shown in Fig. 19-38 can be used to operate the same lightbulb from opposite sides of a room.
A rectangular solid made of carbon has sides of lengths 1.0 cm, 2.0 cm, and 4.0 cm, lying along the x, y, and z axes, respectively (Fig. 18-35). Determine the resistance for current that passes
In an RC circuit, current flows from the battery until the capacitor is completely charged. Is the total energy supplied by the battery equal to the total energy stored by the capacitor? If not,
Two aluminum wires have the same resistance. If one has twice the length of the other, what is the ratio of the diameter of the longer wire to the diameter of the shorter wire?
What is the main difference between an analog voltage meter and an analog ammeter?
A length of aluminum wire is connected to a precision 10.00-V power supply, and a current of 0.4212 A is precisely measured at 20.0oC. The wire is placed in a new environment of unknown temperature
A 10.0-m length of wire consists of 5.0 m of copper followed by 5.0 m of aluminum, both of diameters 1.0mm. A voltage difference of 85 mV is placed across the composite wire. (a) What is the total
What is the main difference between an analog voltage meter and an analog ammeter?
For some applications, it is important that the value of a resistance not change with temperature. For example, suppose you made a 4.70-kΩ resistor from a carbon resistor and a Nichrome
The heating element of an electric oven is designed to produce 3.3kW of heat when connected to a 240-V source. What must be the resistance of the element?
Explain why an ideal ammeter would have zero resistance and ideal voltmeter infinite resistance.
What is the maximum power consumption of a 3.0C portable CD player that draws a maximum of 320mA of current?
What is the maximum voltage that can be applied across a 2.7.kΩ resistor rated at ¼ watt?
A voltmeter connected across a resistor always reads less than the actual voltage across the resistor when the meter is not present. Explain.
(a) Determine the resistance of, and current through. A 75-W lightbulb connected to its proper source voltage of 120 V.(b) Repeat for a 440-W bulb.
A 115-V fish-tank heater is rated at 110 W. Calculate (a) The current through the heater when it is operating and(b) Its resistance?
A small battery- operated flashlight requires a single 1-5-V battery. The bulb is barely glowing, but when you take the battery out and check it with a voltmeter, it registers 1.5V, how would you
A 120-V hair dryer has two settings; 850 W and 1250W. (a) At which setting do you expect the resistance to be higher? After making a guess, determine the resistance at (b) The lower setting; and(c)
You buy a 75-W lightbulb in Europe, where electricity is delivered to homes at 240V. If you use the lightbulb in the United States at 120 V (assume its resistance doe4s not change), how bright will
Calculation the terminal voltage for a battery with an internal resistance of 0.900Ω and an emf of 8.50V when the battery is connected is series with (a) An 81.0- Ω resistance, (b) An
How many kWh of energy does a 550-W toaster use in the morning if it is in operation for a total of 15 mints? At a cost of 9.0 cents/kWh, estimate how much this would add to your monthly electric
Four 1.5-V cells are connected in series to a 12-Ω lightbulb. If the resulting current is 0.45 A, what is the internal resistance of each cell, assuming they are identical and neglecting the
What is the internal resistance of a 12.0-V car battery whose terminal voltage drops to 8.4V when the starter draws 75A what is the resistance of the starter?
At $0.095 per kWh, what does it cost to leave a 25-W porch light on day and night for a year?
An ordinary flashlight uses two D-cell 1.5-V batteries connected in series as in Fig. 18-4b (Fig. 18-36). The bulb draws 450mA when turned on.(a) Calculate the resistance of the bulb and the power
A 1.5-V dry cell can be tested by connecting it to a low-resistance ammeter. It should be able to supply at least 22 A. what is the internal resistance of the cell in this case, assuming it is much
What is the total amount of energy stored in a 12-V, 85- A ∙ h car batter when it is full charged?
How many 100-W lightbulbs, connected to 120V as in Fig. 18-20, can be used without blowing a 15-A fuse?
An extension cord made of two wires of diameter 0.129cm (no. 16 copper wire) and of length 2.7m (9ft) is connected to an electric heater which draws 15.0A on a 120-V line. How much power is
A power station delivers 620kW of power at 12,000 V to a factory through wires with total resistance 3.0 Ω. How much less power is wasted if the electricity is delivered at 50,000 V rather than
The current in an electromagnet connected to a 240-V line is 17.5 A. At what rate must cooling water pass over the coils if the water temperature is to rise by no more than 7.50Co?
Four 240-Ω lightbulb are connected in series. What is the total resistance of the circuit? What is their resistance if they are connected in parallel?
A small immersion heater can be used in a car to heat a cup of water for coffee or tea. If the heater can heat 120mL of water from 25oC to 95oC in 8.0min,(a) Approximately how much current does it
Three 45-Ω lightbulb and three 75-Ω lightbulb are connected in series. (a) What is the total resistance of the circuit? (b) What is their resistance if all six are wired in parallel?
Calculate the peak current in a 2.2-kΩ resistor connected to a 220-V rms ac source.
A 650-Ω and a 2200-Ω resistor are connected in series with a 12-V battery. What is the voltage across the 2200-Ω resistor?
An ac voltage, whose peak value is 180 V, is across a 330-Ω resistor. What are the rms and peak currents in the resistor?
Estimate the resistance of the 120-Vrms circuits in your house as seen by the power company, when (a) Everything electrical is unplugged, and(b) There is a long 75-W lightbulb burning.
The peak value of an alternating current in a 1500-W device is 5.4 A. What is the rms voltage across it?
Given only on 25-Ω and one 35-Ω resistor, list all possible values of resistance that can be obtained?
An 1800-W is welder is connected to a 660-V rms ac line. Calculate (a) The peak voltage and(b) The peak current.
(a) What is the maximum instantaneous power dissipated by a 3.0-hp pump connected to a 240-V rms ac power source?(b) What is the maximum current passing through the pump?
Suppose that you have a 680-Ω, a 940-Ω and a 1.20-kΩ resistor. What is? (a) The maximum, and (b) The minimum resistance you can obtain by combining these?
A heater coil connected to a 240-V rms ac line has a resistance of 34 Ω. (a) What is the average power used? (b) What are the maximum and minimum values of the instantaneous power?
Suppose that you have a 6.0-V battery and you wish to apply a voltage of on 4.0V. Given an unlimited supply of 1.0-Ω resistance, how could you connect then so as to make a ‘’voltage
A 0.65-mm-diameter copper wire carries a tiny current of 2.3 μA. What is the electron drift speed in the wire?
Three 240-Ω resistors can be connected together in four different ways, making combination of series and/or parallel circuits. What are these four ways, and what is the net resistance in each
A 5.80-m length of 2.0-mm-diameter wire carries 750-mA current when 22.0mV is applied to its ends. If the drift speed is 1.7 X 10-5 m/s. Determine(a) The resistance R of the wire,(b) The resistivity
A battery with an emf of 12.0V shows a terminal voltage of 11.8V when operating in a circuit with two lightbulb rated at 3.0 W (at 12.0V) which are connected in parallel. What is the battery’s
At a point high in the Earth’s atmosphere, He 2+ ions in a concentration of 2.8 X 1012/m3 are moving due north at a speed of 2.0 X 105 m/s. Also, a 7.0 X 1011/m3 concentration of O2 ions is moving
Eight identical lights are connected in series across a 110-V line.(a) What is the voltage across each bulb?(b) If the current is 0.50A, what is the resistance of each bulb, and what is the power
What is the magnitude of the electric field across an axon membrane 1.0 X 10-8 m thick if the resting potential is – 70mV?
A neuron is stimulated with an electric pulse. The action potential is detected at a point 3.40 cm down the axon 0.0052s later. When the action potential is detected 7.20 cm from the point of
Eight lights are connected in parallel to a 110-V source by two ling leads of total resistance 1.6 Ω. If 240mA flows through each bulb, what is the resistance of each, and what fraction of the
Estimate how much energy is required to transmit one action potential along the axon of Example 18-15.

Showing 2200 - 2300 of 8946

First
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
Last

Get In Touch

About Us
Contact Us
Career
Jobs
FAQ
Campus Ambassador

Company Info

Security
Copyrights
Privacy Policy
Terms & Condition
SolutionInn Fee
Scholarship

Services

Sitemap
Fun
Definitions
Become Tutor
Study Help Categories
Recent Questions
Expert Questions

Copyright © 2024 SolutionInn All Rights Reserved.

Get the SolutionInn - Study Help App