A Proton of charge +1, as shown in Figure 10 below, starts from rest and loses an EPE of 8.35 x 10 14 Joules, thereby gaining kinetic energy as it moves from Point B to Point A. * I.-'f S Figure 10 Note: Charge of a proton equals + 1.6 x 1019. Mass of proton equals 1.673 x 10'27kg. A. What is the final speed of proton (vy)? B. Calculate the Potential Difference (in Volt) between B and A in the electric field. [Show all the work, including the equations used and the substitution with units.] _A 60 kg girl and her 45 kg brother are at rest at the center of a frozen pond. The boy pushes his sister so that she slides aways (vg) at 2.4 m/s in the left direction while he slides in the opposite direction with velocity v, m/s. Ignore friction. mg=60kg. mp=45kg. Figure 13 A. What is the velocity of the boy (vy) after he pushes his sister? Use conservation of momentum equation. B. Whatis the total change in energy A (K E) after the boy pushes her sister? Use Change in Energy equation. C. What is the work done in this activity? Use Work - Energy theorem. 2 3 4 5 6 7 8 9 10 1 12 3 14 Velocity (m/s) Time (s) Figure 5 Answer the two questions below based on the above Figure 5 which shows the velocity versus time for an object moving in a straight line. 1. At what time after t = 0, does the object again passes through its initial position? Here you have to find a time t after t =0 such that the net displacement is zero. Also note the area under velocity vs. time graph gives the displacement. A. 3s B. 5s C. 7s D. 8.5 s E. 10.5 s 2. During which time interval does the particle have the same acceleration as the one during the time period 12s