Why are we not harmed when we put our hands across a car battery? ( ) we have low resistance ( ) the battery has low voltage ( ) the battery has high resistance ( ) the battery has low current The cost of energy from a flashlight battery is closest to: ( ) 14 cents per kWh ( ) 5 cents per kWh ( ) 14 dollars per kWh ( ) 1000 dollars per kWh A high-fidelity stereo speaker produces sound by: ( ) the force of a magnetic field on electric current ( ) the force of an electric field on an electric charge ( ) the force of a magnetic field on an electric charge Current is measured by: ( ) volts ( ) calories ( ) amps ( ) watts ( ) ohms When you increase the distance between two charges by a factor of 4, the force between them: ( ) is two times less ( ) is four times less ( ) is sixteen times less ( ) is the same Static electricity occurs when two surfaces rub against each other and: ( ) protons flow from one to another ( ) electrons flow from one to another ( ) positrons flow from one to another ( ) neutrons flow from one to another Radio waves and x-rays have the: ( ) same frequency ( ) same speed ( ) same wave length ( ) same energy ( ) none of the above The north geographic pole of the Earth ( ) is a south magnetic pole ( ) has always had the same polarity ( ) is exactly at the magnetic pole ( ) none of the above Shannon is famous for having invented or discovered (among other things): ( ) GPS ( ) Global Hawk ( ) the sound channel ( ) the bit To place a kilogram into space, using an optimum method, should take how much gasoline fuel? ( ) about 1 gram ( ) about 1 kilogram ( ) about 25 kilograms ( ) about 100 kilograms A rocket is a wasteful method for sending things to space. The energy it takes, using a rocket, compared to using an elevator, is a factor of: ( ) 25 ( ) 100 ( ) 250 ( ) 1000 A north magnetic pole is placed 1 cm from a south magnetic pole. The force is: ( ) attractive ( ) repulsive ( ) zero ( ) attractive or repulsive, depending on the angle 2. The North Pole of the Earth is ( ) a north magnetic pole ( ) a south magnetic pole ( ) the Earth is not magnetized because the temperature is above the Curie point ( ) a north magnetic pole now, but it used to be a south magnetic pole 3. To make a north magnetic pole without a south magnetic pole, ( ) cut a permanent magnet in half ( ) create a magnetic field from a solenoid ( ) create a magnetic field from a straight wire ( ) give up it cant be done, as far as we know. Tesla argued that AC was superior to DC because ( ) it was less dangerous ( ) it had less flicker ( ) it could be used for electrocutions ( ) its voltage could be transformed AC stands for ( ) Alternating Current ( ) Alternative Current ( ) Accelerated Current ( ) Awful Current The Van de Graaff did not kill Prof. Muller because ( ) the voltage was not sufficiently high ( ) the high voltage did not last long enough ( ) it was DC rather than AC ( ) he doesnt mind if it hurts