Answer:
Please refer to the figure.
q1 is a negative charge, and q2 and q3 are positive charges. So, the force exerted by q1 on q3 is attractive, and the force exerted by q2 on q3 is repulsive, which means F13 is directed towards left, and F23 is also directed towards left.
The net force on q3 is the sum of these two forces:
Since both forces are directed towards left, their sign should be negative.
Answer:
or -0.000250 C
Explanation:
The field points downward, which is the direction of a positive charge. In order for the penny to rise, it has to have a negative charge since its direction is opposite that of the field.
To calculate the magnitude of the charge:
The penny is to accelerate upward so it must overcome gravity. Hence, the net force to cause it to accelerate it upward is the difference between the electrostatic force and its weight.
Now, the electric field intensity is given by
where q = charge
to 3 significant figures.
In standard form, q = The negative sign indicates it has a negative charge, as explained initially.