Overview
The website we will be using is Pivot. The website is listed here: https://www.pivotinteractives.com/
I will provide you the logins. you should solve it there. After you solve submit. (You are to do lab 4 and lab 5 )
Lab 4, Intro Description:
This lab will connect a force with an acceleration. The simulation video shows a frictionless glider being projected out by a fan. The string is cut and the fan glider moves across the screen where it is caught by the hand. The goal of the lab will be to measure how much force is being produced by the fan and how much acceleration the glider has. The first few questions will ask about the setup and how the fan moves across the screen. #4 tells you that in order to measure the relationship between force and acceleration, something must be kept constant. Using the equation for Newton's 2nd Law (F=ma), what must be held constant so that force and acceleration can vary? #5 asks you about how to measure an acceleration from the tools given. Think critically about how to do this as you will notice there is no tool to measure acceleration directly.
Hint: You only have rulers and time. What equation could solve for acceleration with only a rule and time? Check you kinematics options.
As you analyze the video to collect your data, use the directions given in the lab. You are graph force and acceleration. Create the graph correctly with each axis containing the right variable. From a previous questions, what must be held constant to graph this shape correctly? That previous question should be used here - keep that variable constant. From the video settings, change the fan force to read a different value. Force can be read directly from the scale when the glider stretches the spring. Acceleration can be calculated in the same way as you described it before. (If you didn't know that answer or you feel unsure, reach out to your instructor for help.)
After creating the graph and applying a curve fit (What kind of shape should be created here?), you can analyze your equation and graph. #3 asks about replacing the variables in your equation with actual variables from physics. The hint written in the lab is a good reference as you write an equation. You are not trying to solve an equation, you are trying to write down your curve fit and replace Y and X variables with the variables from class.
Lab 5, Intro Description:
This lab will analyze the two major types of friction: Static vs Kinetic. Static friction is when an object remains stationary and does not move when a force is applied to it. Static friction opposes the motion that would be created if the force was strong enough. Kinetic friction is when an object is moving and a force acts against its motion to slow it down. The simulation here is a plastic toy figure on a rough surface. As an angle increases in the ramp, the toy figure will start to slide down the rough surface. The goal is to measure the coefficient of static friction and the coefficient of kinetic friction. This can be done in a few different ways. Make sure to convert your distance into meters for your calculations.
- If you would like to graph your results using a table and then create a graph, that would be one approach. From the graph, you can apply a curve fit and find the value of the coefficient.
- You can do this completely mathematical without a graph. You would need to create an equation/series of equations that could solve for the coefficient. From there, you can gather the needed information from the video by using the tools feature to measure different items.
Hint: The goal is to measure 2 different coefficients, static and kinetic. You will be required to do both methods, which means you will need to analyze the video twice, once to find the static and once to find the kinetic. You can gather all the data together or do them separately.
You must draw a FBD for this lab for when static friction is present and for when kinetic friction is present. You can upload an image or describe your work in the text box. Be specific in your description (if typing your answer). Saying "it goes up" is notcorrect because there is no force listed, and "up" might not mean vertically straight up. Use words like "parallel", "perpendicular", "up the ramp/down the ramp".
You must measure some item from the video to calculate the static friction coefficient. Use your notes/examples to help you. As you measure the kinetic friction coefficient, you will need some form of trigonometry and rule/time to find this value. Since kinetic friction has motion, you will need to analyze that as you solve for your variable. Note: For this lab you can tilt the ruler to go with the ramp directly. This will help for measuring the distance the toy figure moves down the ramp.
Hint: Use ideas from the previous lab here. You need to find an acceleration and you only have rulers and stopwatches to use. How can acceleration be found when you can only measure distance and time? Check kinematics!