Two radar pulses sent out from the earth at 6:00
A.M. and 8:00 A.M. one day bounce o an alien spaceship and
are detected on earth at 3:00 P.M. and 4:00 P.M. You are not
sure, however, which re
ected pulse corresponds to which emitted
pulse. Is the spaceship moving toward earth or away? If its speed
is constant(less than the speed of light), when will it (or did it)
pass by the earth?1 AnswerPhysics10 years ago
Explain why Federal Reserve Banks are central, quasi-public, and bankers’ banks.1 AnswerEconomics1 decade ago
Explain price leadership as a form of tacit collusion.1 AnswerEconomics1 decade ago
Research the typical energy capacity of a 9 V alkaline battery. Based on your quiescent power requirements, determine the amount of time required by the USB charger circuit to completely drain a fresh 9 V battery without any load connected to the USB port.
Instead of a resistor, use a small flashlight bulb. To light the bulb for a perceptible time, use a large capacitor (approximately 1 F). Collect data. Explain the shape of the graph.
What percentage of the initial potential remains after one time constant has passed? After two time constants? Three?
What was the effect of reducing the resistance of the resistor on the way the capacitor discharged?
Try different value resistors and capacitors and see how the capacitor discharge curves change.
1 Try two 10 F capacitors in parallel. Predict what will happen to the time constant. Repeat the discharge measurement and determine the time constant of the new circuit using a curve fit.
2.Try two 10 µF capacitors in series. Predict what will happen to the time constant. Repeat the discharge measurement and determine the time constant for the new circuit using a curve fit.3 AnswersPhysics1 decade ago