Answer:
Explanation:
A charge located at a point will experience a zero electrostatic force if the resultant electric field on it due to any other charge(s) is zero.
is located at the origin. The net force on it will only be zero if the resultant electric field intensity due to 
and 
at the origin is equal to zero. Therefore we can perform this solution without necessarily needing the value of .
Let the electric field intensity due to be +
and that due to be -
since the charge is negative. Hence at the origin;
From equation (1) above, we obtain the following;
From Coulomb's law the following relationship holds;
where 
is the distance of from the origin, 
is the distance of from the origin and k is the electrostatic constant.
It therefore means that from equation (2) we can write the following;
k can cancel out from both side of equation (3), so that we finally obtain the following;
Given;
Substituting these values into equation (4); we obtain the following;
Answer:
i. The error is the rough convex mirror.
ii. This should be replaced with a smooth convex morror.
Explanation:
Reflection is dependent on the surface involved and has two types; diffuse and specular. When the surface is rough, diffused reflection is observed. The surface causes a distortion of the incident light (the rays would be reflected at different angles to one another) after reflection. This makes some rays to interfere with one another. While specular reflection is observed with a smooth surface.
In the statement, the rough convex mirror would produce a distorted reflection which would produce diffused reflection. The effect is that few or no rays (depending on the degree of how rough the surfce is) would be reflected to the other smooth, flat diagonal mirror.
I'm assuming it was to keep the data consistent? The further you are from a heat source the less heat will get to you as the temperature tries to reach equilibrium and the waves start to spread out, so you should keep everything the same distance to get consistent results. I don't have any information so this is just my assumption
