Part A Click on the + sign next to Energy Graph to show the energy of the pendulum. For all parts, set Gravity g at 9.80 m/s. The setting for Earth for g is 9.81 m/s, so click on the left arrow next to the Gravity slide to change it to 9.80. Also, be sure that friction is set to none for all parts. Drag the pendulum to an angle (with respect to the vertical) of 30, and then release it. When the pendulum is at -30, what form(s) of energy does it have? Check all that apply. Thermal energy Potential energy Kinetic energy Submit Previous Answers Completed Part B Drag the pendulum to an angle (with respect to the vertical) of -30 and then release it. Where is the pendulum swinging the fastest? at 0 at -30 at 30 at 15 Submit Previous Answers Completed Part C Drag the pendulum to an angle (with respect to the vertical) of 30, and then release it. Select to show the acceleration vector. With the pendulum swinging back and forth, at which locations is the acceleration equal to zero? The acceleration is never equal to zero as it swings back and forth. The acceleration is zero when the angle is 0. The acceleration is zero when the angle is either +30 or -30. Submit Previous Answers Completed Part D With the pendulum swinging back and forth, how does the tension of the rope compare to the force of gravity when the angle is 0? View Available Hint(s) The tension is greater than the force of gravity. The tension is less than the force of gravity. The tension is greater than the force of gravity only if it is swinging really fast. The tension is equal to the force of gravity. Submit Previous Answers Part E Drag the pendulum to an angle (with respect to the vertical) of 90, and then release it. With the pendulum swinging back and forth, where is the tension equal to zero? The tension is zero when the angle is 0. The tension is zero when the angle is +45 and -45. The tension is zero at the angles +90 and -90. The tension is never zero. Submit Completed Part F Previous Answers Now, for next parts, you will investigate how the period of oscillation depends on the properties of the pendulum. The period of oscillation is the amount of time it takes for the pendulum to take a full swing, going from the original angle to the other side, and returning to the original angle. You can determine the period by selecting the stopwatch. With the pendulum swinging, you can start the stopwatch when the pendulum is at its original angle and time how long it takes to complete 10 swings. The period will be this time interval divided by 10 (this method is more accurate than trying to time one swing). Set the length of the pendulum to 1.0 m and the mass to 1.00 kg. Click Reset, and then drag the pendulum to an angle (with respect to the vertical) of 30 and release it. What is the period of oscillation, with 2 sig.fig? 4.0 s 0.5 s 2.0 s 1.5 s 1.0 s 20.0 s Part G Drag the pendulum to several other angles (with respect to the vertical): 5, 15, 45, 60 and 75, then release it and measured each period. How does the period of oscillation depend on the initial angle of the pendulum when released? The period is shorter when the initial angle is greater. The period is longer when the initial angle is greater. The period is independent of the initial angle. Submit Previous Answers Completed Part H Comment on your results on the period of the pendulum from the previous Part G. Does the period depend on the initial angle? Does your conclusion contradict what you've learned about simple harmonic oscillators? Essay answers are limited to about 500 words (3800 characters maximum, including spaces). 3800 Character(s) remaining Learning Goal: Analyze the relationships of the energies, forces, accelerations, and velocities of an oscillating pendulum, and determine how the motion of a pendulum depends on its mass, length of the string, and initial angle. For this tutorial, use the PhET simulation Pendulum Lab. This simulation mimics a real pendulum and allows you to adjust the initial position, the mass, and the length of the pendulum. Start the simulation. Length 1 070m Re St Trace Pendulum Lab Noma Os Mass 1 1000 Gravity Ne Friction Ne PHET The Intro tab opens by default. Double click on the Lab tab at the bottom of the screen. You can drag the pendulum to an arbitrary initial angle and release it from rest. You can adjust the length and the mass of the pendulum using the slider bars at the top of the panel. Velocity and acceleration vectors can be selected to be shown, as well as the forms of energy. Feel free to play around with the simulation. When you are done, click the Reset button.