To determine which expressions correctly represent variations of Ohm's law, let's recall the fundamental concepts related to Ohm's law and formulas involving electrical circuits:
1. Ohm's Law: The fundamental equation is [tex]\( V = IR \)[/tex], where:
- [tex]\( V \)[/tex] is the voltage across the resistor (in volts).
- [tex]\( I \)[/tex] is the current flowing through the resistor (in amperes).
- [tex]\( R \)[/tex] is the resistance (in ohms).
2. Power in an Electrical Circuit: There are three main power equations derived from Ohm's law:
- [tex]\( P = IV \)[/tex] (Power is the product of current and voltage)
- Using [tex]\( V = IR \)[/tex], you can transform the power equation into two alternate forms:
- [tex]\( P = I^2R \)[/tex] (Power as a function of current and resistance)
- [tex]\( P = \frac{V^2}{R} \)[/tex] (Power as a function of voltage and resistance)
Now let’s analyze each provided expression to see if they align with known formulas:
1. P = IR: This expression is not correct because power (P) should be [tex]\( P = IV \)[/tex] or can be derived as [tex]\( P = I^2R \)[/tex] or [tex]\( P = \frac{V^2}{R} \)[/tex]. The given expression does not match any of these forms.
2. V = IR: This expression is correct as it is the direct statement of Ohm's law.
3. R = IV: This expression is not correct. According to Ohm's law, the resistance [tex]\( R \)[/tex] should be [tex]\( R = \frac{V}{I} \)[/tex].
4. R = \_ \: This appears to be incomplete and cannot be assessed without additional context or correction.
5. I = \_ \: This is also incomplete and cannot be assessed properly.
6. v = 1/: Again, this incomplete expression cannot be assessed due to lack of clarity on variables and context.
Given the above analysis, the only correct expression is:
- [tex]\( V = IR \)[/tex].
Therefore, the expression that correctly represents a variation of Ohm's law is:
- [tex]\( V = IR \)[/tex] (which corresponds to option 2)
So, checking all that apply, we find that only option 2 is correct:
- Result: [tex]\( \boxed{2} \)[/tex]
