# Question

(a) If the mass of 1.0 kg of coal (or any substance) could be completely converted into energy, how many kilo-watt-hours of energy would be produced?

(b) Assume that the average U. S. family of four uses 600 kWh of electric energy each month and that modern power plants are efficient in converting this released energy into electric energy. How long would this mass be able to supply the U. S. public with electric energy?

(b) Assume that the average U. S. family of four uses 600 kWh of electric energy each month and that modern power plants are efficient in converting this released energy into electric energy. How long would this mass be able to supply the U. S. public with electric energy?

## Answer to relevant Questions

In proton– antiproton annihilation, a proton and an antiproton (which has the same mass as the proton, but carries a negative charge) interact, and both masses are completely converted to electromagnetic radiation. ...Suppose, in Fig. 26.4a, that the observer was 600 m to the left of event B, and A and B were separated by 900 m. She observes that the light flash from event B arrives exactly after that from event A. Determine whether these ...In what sense is a laser an “amplifier” of energy? Explain why this concept does not violate conservation of energy. The wavelength at which the Sun emits its most intense light is about 550 nm. Assuming the Sun radiates as a perfect blackbody, estimate (a) Its surface temperature and (b) Its total emitted power. Find the approximate temperature of a red star that emits light with a wavelength of maximum emission of 700 nm (deep red).Post your question

0