# When a wire is connected to 9 volt battery, the current is 0.020 ampere. What is the resistance of the wire?

In order to get the answer to this you must know the equation that gives you the relationship between voltage, current, and resistance.  That equation, which is derived from Ohm's law is

R = v/r

In this equation, I is the current (measured in amperes), v is the voltage, and...

Start your 48-hour free trial to unlock this answer and thousands more. Enjoy eNotes ad-free and cancel anytime.

In order to get the answer to this you must know the equation that gives you the relationship between voltage, current, and resistance.  That equation, which is derived from Ohm's law is

R = v/r

In this equation, I is the current (measured in amperes), v is the voltage, and r is the resistance.  Now that we know that, we can use the information that you have provided to solve this algebraically.

R = 9/.02

When you do the math here, you get 450

Resistance is measured in ohms so your resistance here is 450 ohms.