The loudness<span> of a sound is linked to the size of the vibration which produces it. A big vibration makes a louder sound. Scientists use the word '</span>amplitude<span>' for the size of waves. For waves on water, it is easy to measure the </span>amplitude<span>.</span>
Answer:
Current, I = 2.3 A
Explanation:
We have,
Voltage of the battery in a circuit is 9 volts
Resistance of the circuit is 4 ohms
It is required to find the current in a circuit. When the voltage and the resistance of the circuit is given then we can find the current in it is given by Ohm's law as :

I is electric current

or
I = 2.3 A
So, the current in the circuit is 2.3 A.