Questions from College Physics

Q: You are cooking breakfast for yourself and a friend using a 1

You are cooking breakfast for yourself and a friend using a 1.20 - kW waffle iron and a 0.500 - kW coffeepot. Usually, you operate these appliances from a 110. - V outlet for 0.500 h each day. (a) At...

Q: If 3.25 x 10-3 kg of gold is

If 3.25 x 10-3 kg of gold is deposited on the negative electrode of an electrolytic cell in a period of 2.78 h, what is the current in the cell during that period? Assume the gold ions carry one eleme...

Q: The current in a conductor varies in time as shown in Figure

The current in a conductor varies in time as shown in Figure P17.60. (a) How many coulombs of charge pass through a cross section of the conductor in the interval from t = 0 to t = 5.0 s? (b) What con...

Q: A 120. - V motor has mechanical power output of 2

A 120. - V motor has mechanical power output of 2.50 hp. It is 90.0% efficient in converting power that it takes in by electrical transmission into mechanical power. (a) Find the current in the motor....

Q: A Nichrome heating element in an oven has a resistance of 8

A Nichrome heating element in an oven has a resistance of 8.0 Ω at 20.0°C. (a) What is its resistance at 350°C? (b) What assumption did you have to make to obtain your answer to part (a)?

Q: A length of metal wire has a radius of 5.00

A length of metal wire has a radius of 5.00 x 10-3 m and a resistance of 0.100 Ω. When the potential difference across the wire is 15.0 V, the electron drift speed is found to be 3.17 x 10-4 m/s. On t...

Q: A Styrofoam cup holds 0.275 kg of water at 25

A Styrofoam cup holds 0.275 kg of water at 25.0°C. Find the final equilibrium temperature after a 0.100-kg block of copper at 90.0°C is placed in the water. Neglect any thermal energy transfer with th...

Q: In a certain stereo system, each speaker has a resistance of

In a certain stereo system, each speaker has a resistance of 4.00 Ω. The system is rated at 60.0 W in each channel. Each speaker circuit includes a fuse rated at a maximum current of 4.00 A. Is this s...

Q: A resistor is constructed by forming a material of resistivity 3.

A resistor is constructed by forming a material of resistivity 3.5 x 105 Ω · m into the shape of a hollow cylinder of length 4.0 cm and inner and outer radii 0.50 cm and 1.2 cm, respectively. In use,...

Q: When a straight wire is heated, its resistance changes according to

When a straight wire is heated, its resistance changes according to the equation R = R0[1 + α(T - T0)] (Eq. 17.7), where α is the temperature coefficient of resistivity. (a...