Answer:
The ratio of the diameter of iron to Cu is;

Explanation:
R=(ρL)/A
- R is resistance,
- L is length,
- A is area,
- ρ is resistivity
- d is diameter
from the question the two materials have the same resistance per unit length.

for iron =
for copper
This means we can equate ρ/A for both materials.

re-arranging the equation we have,





True since coulomb's law states that There is electric force between like charges or opposite charges. The negative sign only shows the nature of the force.
<h3>What is the coulombs law ?</h3>
coulombs formula is given by

Now it states that if two charged particles are separated by the distance r and having same or opposite charge will attract or repel each other.
The intensity of the force depend upon the distance and the nature of the charge.
Hence coulomb's law states that There is electric force between like charges or opposite charges. The negative sign only shows the nature of the force.
To know more about coulomb's law follow
https://brainly.in/question/332179
Answer:
1.27 m
Explanation:
Distance = 192 m
number of rotations = 48
Distance traveled in one rotation = 2 x π x r
Where, r be the radius of wheel.
so, distance traveled in 48 rotations = 48 x 2 x 3.14 x r
It is equal to the distance traveled.
192 = 48 x 2 x 3.14 x r
r = 0.637 m
diameter of wheel = 2 x radius of wheel = 2 x 0.637 = 1.27 m
Hello There!
It takes the planet Mars around 24 hours, 37 minutes, 23 seconds to rotate on its axis. This is around the same amount of time that it takes our planet to rotate once on its axis.