The particle with a charge of 3 × 10 to the power of - 6 C passes through two points of electric field a and B successively, and overcomes the electric field force to do work of - 4J of 6 × 10. It is known that the potential of point B is 50V 1 change of electric potential energy 2 change of electric potential energy at point a 3 change of electric potential energy at point a

The particle with a charge of 3 × 10 to the power of - 6 C passes through two points of electric field a and B successively, and overcomes the electric field force to do work of - 4J of 6 × 10. It is known that the potential of point B is 50V 1 change of electric potential energy 2 change of electric potential energy at point a 3 change of electric potential energy at point a

(1) The work done by overcoming the electric field force is 6 × 10-4j, and the electric potential energy is increased by 6 × 10-4j
(2) The electric potential energy of the particle at point B is EB = q Φ B = 3 × 10 to the power of - 6 × 50V = 1.5 × 10 to the power of - 4 J
Eb-ea = 6 × 10 - 4 J
EA = 1.5 × 10 - 4 - 6 × 10 - 4 = - 4.5 × 10 - 4J
(3) Point a potential Φ a = EA / Q = - 4.5 × 10 of - 4 / 3 × 10 of - 6 power = - 300V
E1 = Q1 Φ a = - 3 × 10-6 power × (- 300V) = 9 × 10 of - 4J

In the electric field, the ball with moving charge of 8x10-9c moves from point a to point B, and the work done by the electric field force is 1.6x10-3j
(1) What is the potential difference between the two points? (2) if the charge is - 2.5x10-8c, how much work does the electric field force do? Positive work or negative work?
If f (x) is an increasing function defined on (0, + ∞), and for all x > 0, Y > 0, f (x / y) = f (x) - f (y)
(1) If f (2) is equal to 1, find the inequality f (x + 3) - f (1 / x) < 2
Let the solution set of inequality x2-2ax + A + 2 ≤ 0 be m. if M belongs to [1,4], find the value range of real number a
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1： (2) negative work (5 × 10-1)
2： Let x = 1y = 1, f (1) = f (1) - f (1) = 0

In the electric field, the ball with moving charge of 8x10-9c moves from point a to point B, and the electric field force makes a positive change of 1.5 * 10-7j
When the ball moves from point a to point B with a moving charge of 8x10-9c in the electric field, the electric field force does 1.5 * 10-7j positive work, and then moves the charge from point B to point C, and the electric field force does 4.0 * 10-7j negative work
(1) Which of the three ABC points has the highest potential?
(2) Potential difference UAB =? UBC =? UAC =?

1) Positive charge? C
2)UAB=WAB/q=1.5*10-7/8*10-9=18.75V
UBC=WBC/q=-4.0*10-7/8*10-9=-50V
UAC=UAB=UBC=-31.15V