Answer : The power usage of the headlamp is 45 watts.
Explanation :
It is given that,
Katie wants to buy the right headlamp bulb as a spare for her motorcycle.
The voltage of the motorcycle, V = 12 V
The current flowing through the headlight is measured at 3.75 A
The power of headlamp is given by the product of the voltage and the current flowing in the headlamp.
Mathematically, it is written as :
[tex]P=VI[/tex]
[tex]P=12\ V\times 3.75\ A[/tex]
[tex]P=45\ Watts[/tex]
The power usage of the headlamp is 45 Watts.