When a footballer collides with the goal post, the forces at work are the action and reaction forces. The player will exert an action force on the goal post, and then a reaction force from the goal post will stop the player. The reaction force call will cause pain and even injury to the player.
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,
Vol of sphere = 4/3 pi r^2.density of sphere = mass/volume.mass = densityxvolumesphere 1. mass = density x 4/3 pi 4.5^2sphere 2 5mass = density x 4/3 pi r^25=4/3 pi r^2 divided by 4/3 pi 4.5^25=r^2 divided by 4.5^25x4.5^2=r^2root(5x4.5^2)=r4.5 root 5 = r
Answer:
Perm lasts longer
Explanation:
Cuz a chemical relaxer only lasts a few weeks and a perm lasts a few months hope this helps
