Science Case

Chapter 1 Exercise 4

If the 2012 growth rate were to continue of 1.1%, what would be the population in 2050?

According to the textbook the population would be at about 9 million in "the middle of the present century". And then begin to gradually decrease and then beginning a more gradual decline to sustainable levels.

Chapter 2 Question 3

Find the energy consumption rate for five devices you use every day.

1. Ceiling fan= 100 watts

2. 36 inch television = 133 watts

3. Clothes iron = 1200 watts

4. Dishwasher = 2000 watts

5. Coffee pot = 1100 watts

Exercise 1

If you paid your servants 8 dollars an hour, what would you're cost be for 1kWh of energy be?

100 watts *1kW/1000W = 0.10 kW

Since your servant does work at a rate of 0.1 kW, it would take him/her 10 hours to produce 1kWh of energy

.10kW* 10 hrs. = 1 kWh

$8 per hr. for 10 hours, this makes $80 per kWh.

Exercise 6

Compare the price per kilowatt per hour of gasoline vs. electrical energy

In New York the price of electrical energy is somewhere around .13 cents per kilowatt hour. Therefore when compared to 40kWh/gal the electrical energy is cheaper. I believe this to be the case because gasoline price is so high and we are quickly running out of it in this country.

Chapter 3 Question 4

A) Compare our gravitational potential energy when we're at the summit

The GPEs are the same because we both weigh the same and we both climb the same height of the mountain above the same ground level. This is the case because GPE = Wh = mgh, where W = mg is our weight and h is the height above a common