Questions from College Physics

Q: An ideal neon sign transformer provides 9250 V at 30.0

An ideal neon sign transformer provides 9250 V at 30.0 mA with an input voltage of 115 V. Calculate the transformer’s input (a) Power and (b) Current.

Q: A transformer on a pole near a factory steps the voltage down

A transformer on a pole near a factory steps the voltage down from 3600 V (rms) to 120 V (rms). The transformer is to deliver 1.0 x 103 kW to the factory at 90% efficiency. Find (a) The power delivere...

Q: A transmission line that has a resistance per unit length of 4

A transmission line that has a resistance per unit length of 4.50 x 10-4 Ω/m is to be used to transmit 5.00 MW over 400 miles (6.44 x 105 m). The output voltage of the generator is 4.50 kV (rms). (a)...

Q: The U.S. Navy has long proposed the construction of

The U.S. Navy has long proposed the construction of extremely low frequency (ELF waves) communications systems; such waves could penetrate the oceans to reach distant submarines. Calculate the length...

Q: Construct ray diagrams to determine whether each of the following statements is

Construct ray diagrams to determine whether each of the following statements is true (T) or false (F). (a) For an object at a concave mirror’s center of curvature, the image is real and inverted. (b)...

Q: (a) The distance to Polaris, the North Star,

(a) The distance to Polaris, the North Star, is approximately 6.44 x 1018 m. If Polaris were to burn out today, how many years would it take to see it disappear? (b) How long does it take sunlight to...

Q: The Earth reflects approximately 38.0% of the incident sunlight

The Earth reflects approximately 38.0% of the incident sunlight from its clouds and surface. (a) Given that the intensity of solar radiation at the top of the atmosphere is 1370 W/m2, find the radiati...

Q: The speed of light in vacuum is defined to be c =

The speed of light in vacuum is defined to be c = 299792458 m/s = 1/√μ0є0. The permeability constant of vacuum is defined to be μ0 = 4π x 10-7 N · s2/C2. Use these definitions to calculate the value o...

Q: Oxygenated hemoglobin absorbs weakly in the red (hence its red color

Oxygenated hemoglobin absorbs weakly in the red (hence its red color) and strongly in the near infrared, whereas deoxygenated hemoglobin has the opposite absorption. This fact is used in a “pulse oxim...

Q: The transmission of light energy as it passes through a solution of

The transmission of light energy as it passes through a solution of light - absorbing molecules is described by the Beer–Lambert law which gives the decrease in intensity I in terms...