The total energy required to run New York City for a whole year is roughly 7.5 x 10 17 J. If matter could be converted into pure energy, how many kilograms of matter
would be needed to run the whole city for a year?
1. 2.5 x 10^6 kg
2. 02.5 x 10^9 kg
3. 8.3 grams
4. 8.3 kg

Amplitude is a measure of a waves a; speed b; distance c; energy d; frequency

Alinearly polarized electromagnetic wave has an average intensity of 196 w/m^2. this wave is directed towards two ideal polarizers (in real polarizers, transmission is also effected by reflection and absorption). polarizer a is oriented with its transmission axis at an angle of θ_1=20.8∘ with the incident electric field. polarizer b has its axis at an angle of θ_2=63.0∘ with the incident electric field. what is the average intensity of the wave after it passes through polarizer a? what is the average intensity of the wave after it passes through polarizer b? suppose that the two polarizers a and b are interchanged. what would the average intensity be after passing through both polarizers?

The frequency of the fundamental of the guitar string is 320 hz. at what speed v do waves move along that string?