Answer:
From the formula of force:

since AB and k are constants:

x is a constant of proportionality
• when force is 4N, separation distance is 1

therefore, equation becomes

when r is doubled, r becomes 2. find F:

- Magnitude: 12.1 N.
- Direction: 17.0° to the 8 N force.
<h3>Explanation</h3>
Refer to the diagram attached (created with GeoGebra). Consider the 5 N force in two directions: parallel to the 8 N force and normal to the 8 N force.
.
.
The sum of forces on each direction will be the resultant force on that direction:
- Resultant force parallel to the 8 N force:
. - Resultant force normal to the 8 N force:
.
Apply the Pythagorean Theorem to find the magnitude of the resultant force.
(3 sig. fig.).
The size of the angle between the resultant force and the 8 N force can be found from the tangent value of the angle. Tangent of the angle:
.
Find the size of the angle using inverse tangent:
.
In other words, the resultant force is 17.0° relative to the 8 N force.
I think it was either Robert Hook or Anton Van Leevwen Hoek
Answer: Scientists found evidence of Earths magnetic field reversal in rocks on the ocean floor at plate boundaries. These rocks have alternating polarity due to magnetization that occurred during their cooling period. Using radio metric dating, scientist estimate that reversals occur approximately every several hundred thousand years.
Explanation:
L=T2xg/4x3.14^2
16x9.8/4x3.14^2
Used your calculator plz