Philadelphia University 1st Homework Renewable Energy Engineering Dept. Date: 17/03/2019 اسم الطالب: Energy Conversion 0611311 الرقم الجامعي: Lecturer: Dr Hasan Maridi

Part1: Choose the correct answer: 1- The British thermal unit (BTU) is a common unit of measurement for thermal energy. If one gallon of gasoline contains 126,000 BTU's, what is the energy content of 15.5 gallons of gasoline? a) 8.13 x 103 BTU's b) 8.13 x 104 BTU's c) 1.95 x 105 BTU's d) 1.95 x 106 BTU's e) 1.95 x 107 BTU's

2- Which of the following are units of energy? Please select all that apply. a) gigawatt b) BTU s-1 c) kWh d) toe y-1 e) N m f) GWy

3- 1000 tonnes of coal are used in a year in a power station. What is the approximate production of electricity in MWh?

a) 7500 b) 2850 c) 2.85

4- The unit of the heat is [°C, Kelvin, Joule, calorie]

5- The unit of the Temperature is [°C, Kelvin, Joule, calorie]

6- The temperature of 4k is equals [ -269 °C, -300 °C , -310°C]

7- The required to heat 5Kg of water from 0°C to 80°C is [ 1672 J, 1672 cal, 1672 Btu] 8- Dr. Hasan Maridi has a mass of 60 Kg, so its weight is a) 588 N b) 9.8 m/s2 c) 60 N d) 6.2 m/s2

Part2: Solve the following problems: 1- Name three examples of other fuels that contain chemical energy.

2- Show that the value of the speed of light is 671,224,363 miles per hour.

3- Specific heat capacity for water is 4200 joule/(kg × kelvin). To increase the temperature of 0.33 kilogram (330 millilitre) of water by 50 celsius, how much thermal energy is needed?

4- A 50 Kg hiker climbed a mountain 1200 m high . He reached the peak in 4 hr, a) Calculate the external work done by the climber. b) Calculate the power generated by the climber.

5- The total amount of energy consumed in the U.S. in 1990 was about 80 quadrillion British thermal units. If one British thermal unit is equivalent to 1055 joules, express this annual energy consumption in joules.

6- An automobile has a horsepower rating (power) of 100 hp. Calculate its power in watts.

7- Show that 1 kilowatthour (kWh) is equivalent to 3.6 megajoules (MJ).

8- A 100-W light bulb is left on overnight. How much energy does it consume and how much money does this cost, if electricity costs 10 cents per kilowatthour?

9- A 50-hp electric motor is used to pump groundwater into a storage tank. Estimate the work done by the pump in Btu/h, kW, and J/s.

10- Convert the following units: (a) 4 km to miles, (b) 100 ft3/day to cm3/h, (c) 1000 L to gal.

GOOD LUCK Dr. Hasan Maridi