An 1800-Watt hair dryer is used for 15.0 minutes. How much energy was used in kilo-calories (food calories)?

Some outdoor security lights are kept on overnight - 7 hours. They use 164 watts of power (figure out how much energy do they consume). If electricity costs $.10 per kilowatt hour, what is the electricity cost for these lights?  Please include two decimal places in your answer.

A kilowatt-hour (kWh) is a unit of measure equal to one thousand watts of electricity being used in one hour. Power companies use this measurement to determine your home energy bill. Consider using a bike for power: It takes 6 minutes pedalling at 24-26 volts consistently to produce just 1/10 (0.1) of a kWh. An average home uses about 25 kWh a day. How long would someone have to pedal at 24-26 Volts to power an average home?

What is the kinetic energy of a 21 kg dog that is running at a speed of 7.6 m/s (about 17 mi/h)?

Water flows over a waterfall that is 20.0 m high at the rate of 4.0 x 104 kg/s. If this water powers an electric generator with a 40.0% efficiency, how many watts of electric power can be supplied? Give you answer in MW (1 megawatt = 1x10' W). 3,136,000

Two railroad cars, each of mass 7495kg and traveling 82.8km/h opposite directions, collide head-on and come to rest. How mu thermal energy is produced in this collision?

On a particular day, the following appliances are used for the times indicated: a 1600-W coffee maker, 12 min, and a 1100-W microwave oven, 3.9 min. With these power requirements, find how much it costs to use these appliances at an electrical cost of 6¢ per kWh. (Do not round your final answer. Fractional cent values are acceptable.)