There are two point charges in vacuum, Q1 = + 4.0 times 10 to the power of - 8C and Q2 = - 1.0 times 10 to the power of - 8C, which are fixed at x = 0 and x = 6cm respectively Why is the electric intensity always along the positive direction of x-axis between 0-6cm?

There are two point charges in vacuum, Q1 = + 4.0 times 10 to the power of - 8C and Q2 = - 1.0 times 10 to the power of - 8C, which are fixed at x = 0 and x = 6cm respectively Why is the electric intensity always along the positive direction of x-axis between 0-6cm?

The direction of judgment force is to put a positive charge, and its force direction is the direction of electric strength. The repulsive force between Q1 and positive charge and the attractive force between Q2 and positive charge are in the x-axis positive direction when the positive charge is between 0 and 6cm

As shown in the figure, Q1 = 2 × 10 ^ - 12C, Q2 = - 4 × 10 ^ - 12C, and the distance between Q1 and Q2 is 12cm. Calculate the field strength and direction of a, B and C,
Where a is the midpoint of q1q2, B is the point 6cm to the left of Q1, and C is the point 6cm to the right of Q2

According to e = KQ / R ^ 2, the electric field intensity of Q1 at a, B and C points is 5N / C right, 5N / C left and 5 / 9 n / C right respectively, and the electric field intensity of Q2 at a, B and C points is 10N / C right, 10 / 9N / C right and 10N / C left respectively. Therefore, the combined electric field intensity of a, B and C points is 15N / C right, (5-10 / 9) n respectively

A charged ball is suspended by an insulated light rope. The mass of the ball is 0.01kg, and the amount of charge is + 2 * 10 minus 8 power c
Now add a uniform electric field in the horizontal direction, the insulating rope is 30 degrees from the vertical line when it is balanced, and calculate the field strength of the uniform electric field

The knowledge of trigonometric function is used to solve this kind of problem
First draw the force analysis diagram, the ball is subjected to the vertical downward gravity mg, the upward tension t along the rope, and the horizontal electric field force F
The three forces are balanced. The resultant force of any two forces is equal to the third force in the opposite direction
The resultant force of gravity and electric field force is equal to the tensile force, and the direction is opposite
F/mg=tan30º
F=Eq

+The two balls of the minus 11 Power C of 4.0x10 and the minus 11 Power C of - 6.0x10 contact and then separate to calculate the charge distribution of the two balls!
The charges counteract each other. We can understand why the remaining charges are divided equally and what force makes more negative charges run to another small ball. Please explain why

After the two balls contact, the amount of charge is divided equally; because the charges of the two balls are opposite at the beginning, the positive and negative offset the amount of charge with smaller absolute value, and then the amount of charge is divided equally. So the two balls in this question first offset the charge of + 4.0 * 10 ^ (- 11) C, that is, the total amount of charge after contact is - 2.0 * 10 ^ (- 11) C, so the amount of charge of the two balls after separation is - 1.0 * 10 ^ (- 11) C