A point charge q1 = 3.90 nC is placed at the origin, and a second point charge q2 = -2.95 nC is placed on the x-axis at x = +20.0 cm. A third point charge q3 = 2.10 nC is to be placed on the x-axis between qi and q2. (Take as zero the potential energy of the three charges when they are infinitely far apart.) ▼ Part A What is the potential energy of the system of the three charges if q3 is placed at x = +1 —| ΑΣΦ U= 9.5 107 -8 Submit Previous Answers Request Answer X Incorrect; Try Again ? J

proton A proton traveling in the - x direction approaches a capacitor consisting of two large, oppositely charged metal plates. The circular plates are 6.1 cm apart and each has a radius of 3.4 m. Each plate has a charge |Q| = 9.0 x 10° C. The left plate is positively charged. The proton enters through the capacitor through a small hole in one of the plates at location A with a speed of 4.6 x 104 m/s. What is the speed of the proton, in m/s, when it exits through a small hole at location B?

n a single plane lies a stationary, positive point charge, qs, with two corresponding equipotential curves in the form of circles that both have a common center at the location of qs. The radial distance between the two equipotential circles is 4.0 cm. (See the diagram below.) What is the value for qs? Assume that k = 9.0 x 109 Nm2/C2.    a. 3.3 x 10-10 C   b. 4.4 x 10-10 C   c. 2.0 x 10-12 C   d. 4.4 x 10-9 C   e. 3.3 x 10-11 C

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A E . B X Choose true or false for each statement below about the uniform electric field shown above. true The electrostatic force on a charge is the same at points A and B true The potential difference between points A and B is the same as between points C and B. true The kinetic energy of a positive charge moved from point A to point B will decrease. false The plate on the right is positively charged true ✓ The potential energy of a negative charge moved from point A to point B will increase. Submit Answer Incorrect. Tries 1/2 Previous Tries

Part A A +4.0 µC charge is 22 cm to the right of a -7.8 µC charge. Determine the potential at the midpoint between the two charges. Express your answer to two significant figures and include the appropriate units. µẢ Vmid = Value Units Submit Request Answer Part B Determine the direction of the electric field at the midpoint between the two charges. O to the left. O to the right. Submit Previous Answers v Correct Part C Determine the magnitude of the electric field at the midpoint between the two charges. Express your answer to two significant figures and include the appropriate units. µA ? Emid = Value Units

The ammonia molecule NH3 has a permanent electric dipole moment equal to 1.47 D, where 1 D = 1 debye unit = 3.34 x 10-30 C.m. Calculate the electric potential in volts due to an ammonia molecule at a point 56.2 nm away along the axis of the dipole. (Set V = 0 at infinity.) Number i Units

A 5.60 μF parallel-plate air capacitor has a plate separation of 4.50 mm and is charged to a potential difference of 300 V. Part A Calculate the energy density in the region between the plates, in units of J/m³. Express your answer in joules per cubic meter. VE ΑΣΦ U = Submit Previous Answers Request Answer ? X Incorrect; Try Again; 2 attempts remaining J/m³