Answer:
Explanation: according to Coulomb's inverse-square law is proportional to the square of distance between them and is given by

where r is the distance between the charges & k is the Coulomb's constant
k=1/(4*ε_0*π)
k=9*10^9
the distance between the charges in this question is d_1
hence the magnitude of the force exerted by q_0 on q_1 is given by

due to location of particle 1 above the particle 0 the direction of force is parallel to y axis and in vector form

Decompose the forces acting on the block into components that are parallel and perpendicular to the ramp. (See attached free body diagram. Forces are not drawn to scale)
• The net force in the parallel direction is
∑ <em>F</em> (para) = -<em>mg</em> sin(21°) - <em>f</em> = <em>ma</em>
• The net force in the perpendicular direction is
∑ <em>F</em> (perp) = <em>n</em> - <em>mg</em> cos(21°) = 0
Solving the second equation for <em>n</em> gives
<em>n</em> = <em>mg</em> cos(21°)
<em>n</em> = (0.200 kg) (9.80 m/s²) cos(21°)
<em>n</em> ≈ 1.83 N
Then the magnitude of friction is
<em>f</em> = <em>µn</em>
<em>f</em> = 0.25 (1.83 N)
<em>f</em> ≈ 0.457 N
Solve for the acceleration <em>a</em> :
-<em>mg</em> sin(21°) - <em>f</em> = <em>ma</em>
<em>a</em> = (-0.457N - (0.200 kg) (9.80 m/s²) sin(21°))/(0.200 kg)
<em>a</em> ≈ -5.80 m/s²
so the block is decelerating with magnitude
<em>a</em> = 5.80 m/s²
down the ramp.
Many things can affect a material's resistance, The type of material, how the material is being held (If its laying flat, being pulled, etc). What the material is used for, and how much material there is. Hope this helps!
Magnetic field describea magnet's ability to act at a distance