SPH4U Lesson Assignment #14

SPH4U Lesson Assignment 14 In this assignment you are going to focus on: Magnetic Fields and Electromagnetism. Total Marks: 63 marks Instructions: After completing the lesson action section of your home page, you are ready to complete your lesson assignment. Follow these steps. a) In the textbox given, explain the strategy that you used to determine your answer. b) Fill in your answer. The mark for each question is given at the introduction to the questions to be completed. c) When finished answering all your questions, save your file and upload the file into the appropriate dropbox. Part A (Solving Questions): Multiple Choice: (52 marks) Each question is worth different marks according to the strategy used. If calculations are required, the mark for the strategy will worth more marks and the final answer will be worth one mark. Identify the choice that best completes the statement or answers the question. Your choices are given below the text box. Make sure you include your strategy. ____ 1. (two marks) Which of the following statements about determining the magnetic field around a straight conductor is NOT correct? a. b. c. d. e. ____ The thumb of your right hand that points is pointing in the direction of the current. A compass may be used when it is orientated perpendicular to the conductor. Grasp the conductor with your right hand. Curl the fingers of your right hand in the direction of the magnetic field lines. A compass may be used when it is orientated parallel to the conductor. 2. (two marks) Which of the following statements about the loop shown below is false? (The loop is horizontally oriented.) SPH4U1 Lesson Assignment Page 1 a. b. 0 c. d. e. ____ The north pole of the loop is at the bottom of the loop labelled Z. The direction of the magnetic field cannot be determined. The magnetic field goes up through the loop. The magnetic field is strongest in the inside of the loop. The south pole of the loop is labelled X. 3. (two marks) Which one of the following substances has the highest relative magnetic permeability? a. air b. steel c. copper ____ 4. (two marks) In his experiment, J.J. Thomson demonstrated that cathode rays are deflected by a magnetic field. From this, we know that cathode rays a. contain potential energy b. travel in straight lines c. travel at the speed of light ____ d. carry a charge e. are affected by the force of gravity 5. (two marks) In his experiment, J.J. Thomson demonstrated that cathode rays are deflected by an electric field. From this, we know that cathode rays a. possess potential energy b. travel at the speed of light c. travel in straight lines ____ d. aluminum e. water d. are affected by the force of gravity e. carry a charge 6. (two marks) A magnetic force causes a positively charged particle q to undergo uniform circular motion in a uniform magnetic field B. The radius of the circular motion is r. The magnitude of the positively charged particle’s velocity can be described by which of the following? a. d. b. e. c. SPH4U1 Lesson Assignment Page 2 ____ 7. (five marks) A positively charged particle of mass 3.0 × 10–12 kg and charge +6.4 × 10–5 C is perpendicular to a 1.5-T magnetic field. If the particle has a speed of 4.8 × 103 m/s, the acceleration of this particle is a. 3.4 × 10–4 m/s2 b. 2.6 × 10–20 m/s2 c. 1.5 × 1011 m/s2 ____ 8. (five marks) A proton of charge 1.6 × 10–19 C is moving east with a speed of 8.2 × 107 m/s, as it enters a magnetic field of 2.5 T directed downward. The magnitude and direction of the magnetic force acting on the proton is a. 3.3 × 10–11 N [N] b. 1.9 × 1011 N [S] c. 5.3 × 10–12 N [S] ____ d. 1.5 × 10–4 m/s2 e. 1.7 × 1019 m/s2 d. 3.3 × 10–11 N [S] e. 1.9 × 1011 N [N] 9. (five marks) A electron of charge –1.6 × 10–19 C is moving east with a speed of 8.2 × 105 m/s, as it enters a magnetic field of 1.5 T directed downward. The magnitude and direction of the magnetic force acting on the proton is SPH4U1 Lesson Assignment Page 3 a. 8.7 × 10–14 N [S] b. 2.9 × 10–25 N [N] c. 2.0 × 10–13 N [N] d. 2.0 × 10–13 N [S] e. 2.9 × 10–25 N [S] ____ 10. (five marks) A 5.0-cm straight conductor carries a current of 12 A through a uniform 0.85-T magnetic field. When the angle between the current and the magnetic field is 25°, the magnitude of the force on the conductor is a. 120 N b. 0.22 N c. 86 N d. 0.86 N e. 22 N ____ 11. (five marks) A 50.0-cm straight conductor carries a current of 10.0 A through a uniform magnetic field. The magnitude of the force on the conductor is 0.50 N. The angle between the current and the magnetic field is 50.0°. What is the magnitude of the magnetic field? SPH4U1 Lesson Assignment Page 4 a. 1.9 T b. 190 N c. 0.13 T d. 12 000 T e. 120 T ____ 12. (two marks) Magnetic force is equal to a. d. b. e. c. ____ 13. (two marks) Using the right-hand rule for the motor principle, the right thumb points a. b. c. d. e. toward the north pole of the magnetic field in the direction of the current in the direction of the force toward the south pole of the magnetic field opposite to the direction of the current ____ 14. (five marks) What is the magnitude of the magnetic field in the core of a 10.0 cm long solenoid with 200 turns, carrying a current of 5.00 A? SPH4U1 Lesson Assignment Page 5 a. 1.00 × 102 T b. 1.00 × 104 T c. 7.96 × 107 T d. 5.03 × 10–6 T e. 1.26 × 10–2 T ____ 15. (two marks) If a magnetic field changes near a conducting plate, currents are induced within the plate, forming closed circular paths called a. induction currents b. magnetic fields c. induction fields d. eddy currents e. Lenz’s paths ____ 16. (two marks) Which factor does NOT affect the strength of an electromagnet? a. direction of the windings b. resistance of the coil c. diameter of the coil d. number of turns in the coil e. permeability of the core ____ 17. (two marks) A permanent magnet is held still in the centre of a coil connected to a galvanometer. The galvanometer needle will a. steadily increase b. steadily decrease c. be steady and have a nonzero value SPH4U1 Lesson Assignment d. steadily decrease and then increase e. be steady and have a zero reading Page 6 Part B (Putting the Concepts to Work): Completion ( 11 marks): Using your reading, answer the following questions. Give your answer as well as your strategy for determining your answer. As part of your answer, give the page number in the reference material or the website that you used to find the answer to the question. 1. (four marks) Define one ampere using two long, straight, parallel conductors. 2. (two marks) Define one coulomb. 3. (two marks) State the law of electromagnetic induction. 4. (three marks) State Lenz’s law SPH4U1 Lesson Assignment Page 7