I need clearly visible solutions with graphs. Do not use really excessive formulas this is simple physics. Thank you!

3. Three point charges of 15.0 HC are arranged on the vertices of an equilateral triangle of side length 0.400m, as shown in the diagram below. Determine the net electric force experienced by charge qi due to the other two charges. (3 marks) 91 92 4. Point charge qi has a charge of 2.5 x 10 C, and point charge q2 has a charge of 9.1 x 10-6 C. Point charge q1 is initially at rest and 0.30 m from q2. Point charge q2 has a mass of 3.8 x 109 kg. Both charges are positive with q1 remaining fixed at the origin while q2 travels to the right after being released. Determine the speed of charge q2 when it reaches a distance of 0.45 m from q1. (3 marks) 5. A positive charge Q is fixed to the origin. A negative charge with magnitude 9Q is fixed along the positive x-axis a distance d to the right of the origin. Determine a point where a small positive test charge q will experience zero electrical force from the two charges, or show that there is no such point. Include a diagram and an explanation of the placement of the test charge q. (4 marks) 6. A dust particle with a mass of 2.2 x 10" kg carries a negative charge due to the presence of 3500 excess electrons. It is held in position 6.0 cm from a fixed negative point charge of magnitude 4.0 x 10" C. The particle is then released and is immediately repelled. How fast will it be travelling when it is 10.0 cm from the negative point charge? (4 marks) 7. An oil drop is balanced in a Millikan apparatus. The drop has a mass of 1.8 x 10"* kg. The plates have a potential difference of 920 V, and are separated by 3.6 cm. a. Is the sphere positively or negatively charged? Explain. (1 mark) b. Calculate the magnitude of charge on the sphere. (2 marks) c. How much excess or deficit of electrons does the sphere have? (1 mark) 8. Explain, with the aid of a diagram, how an electric doorbell works. (5 marks) 9. Summarize how the principles of electricity and magnetic force are applied to make a speaker work. What role does electric current play? How is sound produced? (5 marks) 10. A positively charged object moving west on the equator experiences a magnetic force pointing up to the sky. What is the direction of the dominant magnetic field at this location? Explain. (2 marks)