Answer: Use the Right -hand Rule to find the direction of the magnetic field.
Explanation: A magnetic force only occur, in a magnetic field, when a particle is moving perpendicularly relative to the magnetic field. So, all three quantities are perpendicular among themselves.
The Right-Hand Rule apply for the positive charges moving in conventional current. If the moving charge is negative, the velocity must be reversed.
Right-Hand Rule determines the direction of any or all of the three and it is as follows: With you right hand, point your index finger in the direction of the velocity, your middle finger in the direction of the magnetic field and your thumb will be pointing in the direction of the magnetic force.
Another way of using the rule is when there is a current carrying wire:
The fingers of your right hand will curl into a half circle around the wire, they will point in the direction of the field. The thumb will point in the direction of the conventional current.
I think it is because in objects that reflect light, the light is bounces/reflects off the object in one direction and one angle, and hits your eye, causing it to be processed as a reflection of yourself in your brain. But in one that scatters light, it bounces/reflects off in many different directions. Due to this, your brain may not process it as a reflection.
Here is a little bit of extra info:
https://www.sciencelearn.org.nz/resources
<span>Density is entirely unrelated to an object's size. It is a property of a given</span>
As we know that electric field at any point caused due to a point charge given by, kQ/r^2
Where, k is dielectric constant of medium, Q is the point charge and r is the distance between the point charge and point where electric field is to be measured.
Let us assume a charge of q is placed at x=+20cm to make electric field at
x=+10cm zero.
Total electric field at x=+10cm can be shown by equation,
(k X 2.20 X 10^-12)/(10-0)^2 + (k X -4.80 X 10^-12)/(10-(-11))^2 + (k X
q)/(10-20)^2 = 0
=> 2.20 X 10^-14 - 1.09 X 10^-14 + q X 10^-2 = 0
=> q = 1.09 X 10^-12 - 2.20 X 10^-12
=> q = -1.1 X 10^-12 Coulombs or -1.1 pC
