I need HELP with my Homework!!?

Question

IF you can answer these thanks alot!! This might help:
power rating =current x voltage
1. An electric space heater requires 29 A of 120 V current to adequately warm a room. What is the power rating of the heater?
2. A color television has a power rating of 320 W. How much current is in the television when it is connected across 120 V?
3. The operating voltage for a light bulb is 120 V. The power rating of the bulb is 75 W. Find the current in the bulb.
4. The current in the heating element of an electric iron is 5.0 A. If the iron dissipates 590 W of power, what is the voltage across it?

Answer 1

i wont give you the answer but try this. draw a t on a sheet of paper, on top of the t write watts, under the t one the left side write amps, and on the right side write volts--draw another t and on top write volts, under the t on the left write amps, and on the right side write ohms.
if you have amps and volts multiply them to get watts
get it?
if you have amps and ohms multiply the to get volts.
get it?
if you have watts and volts divide to get amps. and so on.
so if you have for #1--3480 watts (power rating) you are on the right track ;)

Answer 2

Maybe you do not understand the relationship between voltage, current (amperes), resistance in ohms and power or wattage.

Think of voltage as pressure, like water presssure. Current is like the current in a river, only it is electrical flow. Resistance is like what happens when a creek is full of rocks. If the creek is smooth, waterflow is not impeded. The wider a creek, the less resistance there is to flow. The larger a wire, the less resistance there is to current (amperes) to flow. Some conductors like copper have fewer rocks in the creek than, say, iron conductors.

Voltage pushes current. Resistance reduces current.

Wattage or power is a measure of energy. A 100 watt light bulb uses more energy than a 50 watt bulb.

Resistance opposes the flow of electricity, an in doing so causes heat (wattage) to be generated. There is a mathmatical formula for this. In fact there are two. Wattage is equal to the voltage applied multiplied by the resistance. Wattage is also equal to the square of the current multiplied by the resistance.

With the first formula, Power=Volts x amps, try to answer the first question now. If you can, fine. Go on to the next. If you have trouble, come back with another question. I will be watching.