A motorcyclist is making an electric vest that, when connected to the motorcycle's 12 V battery, will warm her on cold rides. She is using 0.25-mm-diameter copper wire, and she wants a current of 4.3 A in the wire. What length wire must she use?

8.2 m

Explanation:

We are given that

Potential difference=

Diameter=

Radius=

Current= I=4.3 A

Resistivity of copper wire of

We have to find the length of wire must she use.

We know that

Using the formula

ohm

Using

Hence,  she must use the length of wire =8.2 m

i had this question and the answer was 3.15 miles.

martina travels from school to her mom's office. from there, she walks to school. after school, she walks to the library and then to a friends house before finally ending back at home. find martina's total distance traveled.

a) 0 miles  

b) 0.4 miles  

c) 1 mile  

d) 3.15 miles