Electric current is the flow of electric charge.
Students will be able to:
Explore the scientific definition of work and how it relates to power and energy.
Your students have their own understanding of the words, “work,” “energy” and “power”. They are likely different than those used by scientists, engineers and other people familiar with the scientific definitions.
Work is the transformation or conversion of energy and is measured in joules (J).
Energy is the ability or capacity to do work and is also measured in joules (J). There are many different forms of energy (heat, light, electric, elastic, etc.) but all energy is either potential or kinetic.
Power is the rate at which energy is transformed or the rate at which work is done. Power (P) is measured in watts (W) or joules per second (J/s). Power can be calculated if you know the work (or energy) and time: Power = Energy / time (or P=E/t).
Electrical power is the amount of electrical energy that is changed into other forms of energy every second. A good example of this is a 100-watt light bulb, which changes 100 joules of electrical energy into light and heat every second.
Electrical power can also be calculated if you know the voltage and the current in a circuit. Voltage is represented by ‘V’ and current is ‘I’.
Power = Current x Voltage (or P= I x V)
Assess your students on their participation in classroom discussions, their collaboration with partners and in small groups. Also note their individual ability to build and test a water wheel, then describe how it demonstrates the relationship between potential and kinetic energy.