Online Physics Lab : A charged particle in a uniform electric field

Use informations in PartA (References) and Part B (Data) to answer questions in Part C

- Instructions (Please highlight the underlined website URL and copy and paste since it is not a hyperlink itself)

Go to https://ophysics.com/em6.html

to open your internet browser at Charged Particle in an Electric Field for this exploration

Part A: Protocol (References) + Procedure

In this activity you will investigate the motion of a charged particle in a uniform electric field. You will use a simulation of a charged particle being shot into the electric field created by a capacitor with its initial velocity perpendicular to the direction of the field lines. Background In this simulation charged particles enter the uniform electric field of an ideal capacitor perpendicular to the field lines. This field causes the particles to follow a curved trajectory, similar to the gravitational field causing projectiles to follow a parabolic pathway when their initial velocity is not vertical. The particles may exit at an angle 0 with respect to their original direction, or may hit one of the capacitor plates. Go over Integrated Example 20.15 A cathode-ray tube in Module 4 Lesson 3 to review how to determine the force acting on a charged particle when moving inside a uniform electric field. This simulation applies to the so-called electron deflector from this example, where the charged particle is an electron. Electron deflector + + + +++++ F- E L = 5.0 cm Figure 1 Electron entering with velocity vi the uniform electric field E inside a capacitor and exiting with velocity v2 The motion of the charged particle is similar with the projectile motion: . on the x axis, uniform motion with constant velocity, Vx = v1 on the y axis, accelerated motion with constant acceleration due to the electric force exerted by the electric field on the charged particle. ay Fon q qE m m Instructions Go to https://ophysics.com/em6.html to open your internet browser at Charged Particle in an Electric Field for this exploration. Part 1: Simulation Get familiar with the simulation and the variables you can control.1. Use the sliders to adjust the strength of the field, the distance between the plates of the capacitor creating the uniform field, the initial velocity of the charged particle, its charge and its mass. Investigate how these variables affect the particle's time of travel inside the capacitor or its ability to exit it. 2. Set up the distance between the plates d at 5.0 cm (with 2 sig.fig) and the direction of the field up. 3. Set up the strength of the electric field E (in N/C) based on the first, second and third digits of your student ID followed by one zero digit. You cannot get any mark if you don't correctly select the field. Example: for student number 123456789, the strength of the electric field should 1230. N/C (with 4 sig.fig.) Start with the initial velocity vi at 5.0x105 m/s (with 2 sig.fig.), the charge q of 5.0 JC (with 2 sig.fig.) and the mass m at 2.0x10-16 kg (with 2 sig.fig.) 4. Record in Table 1 your variables, then press run to shoot the particle into the field. Take a screenshot of your result. All variables, as well as the time in the field (in ns) and the pathway of your charged particle should be visible in your screenshot. Include it in your lab report. Charged Particle in an Electric Field time in field = 40 ns Run Reset + UP |Down Show Voltage Show Grid Show Electric Field Intensity Electric Field (N/C) 1230 Distance Between Plates (cm) 5 I em Initial Velocity (x 106 m/9) 5 Charge of Particle (NC) 5 Particle Mass (x10 16 kg) 2 Figure 2 Settings for simulation and pathway of charged particle inside the capacitor producing a uniform electric field 5. Switch the direction of the field, then shoot the particle into the field. Notice any difference in the pathway and travel time from the previous setting. 6. Restore the direction of the field back to up but change the sign of the charge. Notice any difference in the pathway and travel time from the initial setting.7. Change the charge of the particle and the initial velocity so that the particle barely exits the capacitor, as in the following diagram. + Figure 3 Pathway for charged particle that just exits the capacitor 8. Record in Table 2 your variables for this second setting, then take a screenshot of your result. All variables, as well as the travel time (in ns) and the pathway of the particle should be visible in your screenshot. Include it in your lab report. 9. Investigate how the mass, the charge, the initial velocity and the strength of the field affect the particle's pathway. Part 2: Summary 10. Use the recorded time t from Table 2 to calculate Ax and Ay and compare them with L and d/2. 11. Comment on possible discrepancies, even if you don't notice any. 12. Answer the remaining questions on the work file.Part 1 Simulation 1. What is this activity about? 2. List the variables you started with, according to the instructions from the protocol. Title the table Table 1 E (N/C) v, (m/s) q (HC) m (kg) 3. Insert your first screenshot below. All variables and the pathway of your charged particle should be visible. 4. Describe any difference in the pathway and travel time you noticed when you switched the direction of the electric field or the sign of the charge. 5. List the variables you used to make the particle barely exiting the capacitor and the recorded time in the field. Title the table. Table 2 E (N/C) v. (x105 m/s) q (HC) m (kg t (ns) 6. Insert your screenshot below showing the particle barely exiting the capacitor. All variables, as well as the time in the field and the pathway of your charged particle should be visible.\fa. Ax b. Ay 8. Compare Ax and Ay with L and d/2. Comment on possible discrepancies. 9. Complete each statement below to summarize your investigation on how the strength of electric current, initial velocity, charge and mass affect the particle's time of travel inside the capacitor or its ability to exit it. a. When I increased the initial velocity, while keeping all other variables constant, b. When I increased the strength of the electric field, while keeping all other variables constant, c. When I increased the amount of charge of the particle, while keeping all other variables constant, d. When I increased the mass of the particle, while keeping all other variables constant, _ 10. Provide a brief explanation for each of the observations you described in the previous question. Include appropriate formulas/equations/definitions in your explanation. /8 a. b. C. d