A particular extension cord can support up to 8 amps. Mo has an iron whose label states 1200 watts and wonders if the iron can be plugged into the extension cord. If watts are converted to amps by dividing by 120 how many amps does the iron use?

An 1800-Watt hair dryer is used for 15.0 minutes. How much energy was used in kilo-calories (food calories)? (Note that 1 kilo-calorie = 4184 J)

A spring has a spring constant of 25 lbs/in.  How much force does it apply when it is stretched 8 inches?

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

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.)

A 62 kg man climbs the CN tower which is 0.55 km high in 30 min. How powerful is the man?    a) 1.9 X 10¹ W   b) 1.9 X 10² W   c) 1.1 X 10⁴ W   d) 1.9 X 10⁻¹ W

A worker does 100 J of work to move a box up an inclined plane. The amount of work useful  done is 94 J. What is the efficiency of the inclined plane?