A student finds a resistor in an old transistor radio. When the resistor is attached to a 1.5 V cell, the flow of current is measured at 0.025 A. When the resistor is attached to four 1.5 V cells, the current is measured at 0.1 A. When the resistor is attached to a 9 V battery, the current is measured at 0.15 A. Is the resistor an ohmic resistor? Explain how you know.

yes

Explanation:

because no matter what voltage you connect it up to, the current always increases proportionally to the voltage.

this is because it follows ohm's law V = I X R.

(voltage = current X resistance)

so to calculate the resistance, change the formula to R = V / I giving you 60 ohm (resistor value)

the value of the resistor is always 60 ohm's, no matter which combination of voltage and current you used and measured, so it follows ohm's law, therefore being an ohmic resistor