Question Solved1 Answer 1. (100 points) Four identical positive charges q are located on corners of a plastic square of width a. The origin is located at the center of a rectangular as indicated in the diagram. The plastic square is neutral and the polarization of the plastic can be ignored in this problem. У Х a A. How many total electrical forces are there present on all four charges, counting each nonzero force exerted by a particle on a particle as a separate force. B. What is the total net force on the system of four charges? Briefly explain how you know this. C. Calculate the magnitude of the force on charge in the lower-left-hand corner. D. What is the magnitude of the net electric field far r >> a from the square?

Please answer Part A You are a member of a geological team in Central Africa. Your team comes upon a wide river that is flowing east. You must determine the width of the river and the current speed (the speed of the water relative to the earth). You have a small boat with an outboard motor. By measuring the time it takes to cross a pond where the water isnat flowing, you have calibrated the throttle settings to the speed of the boat in still water. You set the throttle so that the speed of the boat relative to the river is a constant 6.00 m/s. Traveling due north across the river, you reach the opposite bank in 20.1 s. For the return trip, you change the throttle setting so that the speed of the boat relative to the water is 8.20 m/s. You travel due south from one bank to the other and cross the river in 11.2 s. How wide is the river? Express your answer with the appropriate units. HA ? d = 99.427 m Submit Previous Answers Request Answer X Incorrect; Try Again; 13 attempts remaining Part B Complete previous part(s) Part C Complete previous part(s) Part D Complete previous part(s) Provide Feedback Next >

A typical laboratory centrifuge rotates at 4000 rpm. Test tubes have to be placed into a centrifuge very carefully because of the very large accelerations.a. What is the acceleration at the end of a test tube that is 10 cm from the axis of rotation?b. For comparison, what is the magnitude of the acceleration a test tube would experience if stopped in a 1.0-ms-long encounter with a hard floor after falling from a height of 1.0 m?

a 3. er What is the slope of the water surface as a function of a, g. , and Pa if the acceleration a points in the positive x and z directions?

(figure 1) shows an acceleration-versus-force graph for three objects pulled by identical rubber bands. The mass of object 2 is 0.10 kg Figure 1 of 1 a (m/s) 1 5- 2 4 3 3 1 0 0 1 2 3 4 5 6 Force (number of rubber bands)

{A moon orbits a planet in the xy plane, as shown in the figure. You want to calculate the force on the moon by the planet at each location labeled by a letter (A,B,C,D). At each of these locations, what are (a) the unit vector f, and (b) the unit vector F in the direction of the force? At A: At B: At D:

A planet of mass 4 ⨯ 1024 kg is at location 5 ⨯ 1011, −4 ⨯ 1011, 0 m. A star of mass 4 ⨯ 1030 kg is at location −6 ⨯ 1011, 5 ⨯ 1011, 0 m. It will be useful to draw a diagram of the situation, including the relevant vectors. (a) What is the relative position vector r pointing from the planet to the star? r = 〈−11·1011, 9·1011, 0〉 m (b) What is the distance between the planet and the star? |r| = m (c) What is the unit vector in the direction of r? = 〈−.774, .633, 0 〉 (d) What is the magnitude of the force exerted on the planet by the star? |Fon planet| = N (e) What is the magnitude of the force exerted on the star by the planet? |Fon star| = N (f) What is the force (vector) exerted on the planet by the star? (Note the change in units.) Fon planet = 〈−3.35, 4.09, 0〉 ⨯ 1020 N (g) What is the force (vector) exerted on the star by the planet? (Note the change in units.) Fon star = ⨯ 1020 N