A moving particle encounters an external electric field that decreases its kinetic energy from 9930 eV to 8130 eV as the particle moves from position A to position B. The electric potential at A is -59.0 V, and that at B is +13.0 V. Determine the charge of the particle. Include the algebraic sign (+ or -) with your answer. Number i Units Lower potential 4 Higher potential VB

Particles A, B, C, and D in (Figure 1) each carry a charge of magnitude 1.0 nC. Express your answer with the appropriate units. U = 0 J Submit Previous Answers Part C Correct Calculate the electric potential energy for the charge distribution in this 3.0-m square if B and C are positive and A and D are negative. Express your answer with the appropriate units. ΜΑ ? U = Value Units Submit Request Answer <1 of 1 Part D Calculate the electric potential energy for the charge distribution in this 3.0-m square if A and C are positive and B and D are negative. Express your answer with the appropriate units. Figure A+ +B HA ? U = Value Units

I Review I Constants A 11.0 nC charge is at x = Ocm and a -1.3 nC charge is at x = 7 cm . Part A At what point or points on the x-axis is the electric potential zero? Express your answer using two significant figures. If there is more than one answer, give each answer separated by a comma. V ΑΣφ Xo = cm Submit Previous Answers Request Answer

44. A metal ramp 6.00 m long is tilted 10.0° and is used to load and unload a moving van. Suppose a 20.0 kg box is pushed up the ramp and it slides with a friction coefficient of 0.30. The ramp can be viewed as a “machine” where the useful output is the potential energy gain of the box and the input is the physical work done by the person doing the pushing. (a) Determine the efficiency of the ramp. (b) Determine the ratio of the force needed to lift the box without the ramp to the force needed to push it along the ramp (this is called the mechanical advantage).