PLTW Unit One Test

In a simple gear train with idler, which of the following statements is true?

• The driven gear is also referred to as the output.

• The middle gear is also referred to as the driving gear.

• The driving gear is also referred to as the output.

• The output gear is where the movement starts.

Refer to the simple gear train set up below. The outer gears rotate in the ____________ direction of the middle gear.

• opposite

• same

• perpendicular

• random

Your group wants to program a motor to drive forward for 2 seconds, stop for 1 second and then drive in the opposite direction for 4 seconds and stop. You create the following code. Will this code execute as you intended?

• Yes, the code will execute as intended.

• No, the code will not execute as intended.

Bailey, Jamal, and Prashad are working together on a complex code for their Res-Q-Bot. It is a code involving many steps that will take several days to complete. Which of the following will help the entire group stay on track?

• The three group members agree that they do not need to write any comments for their code.

• Jamal and Prashad discuss some new ideas for their code but do not write them down.

• Bailey works on the code by herself and finishes it the way she wants it done.

• The three group members agree to create a flow chart so that all group members understand the plan and can work on the code.

Which of the following is an example of a scenario where a robot will move autonomously?

• A coding software program is used to create code and is downloaded to the robot, so that the robot moves based on the code.

• A coding software program is used to create code, and a person pushes the robot with their hands so that it moves faster.

• A coding software program is used to create code but is not downloaded to the robot.

• A person uses a handheld device to drive the robot, no coding software is used.

Sophia and Jin are attempting to create an algorithm to make their robot do a shuffle with the following requirements: 1. It must last more than 20 seconds. 2. It must go both forward and backwards. 3. The algorithm begins when BumperA is pressed. Which of the following must be true of the algorithm?

• The event handler block must include “When Brain left button is pressed”.

• The “wait time” of all the actions must add up to 15 seconds.

• The event handler must include a loop.

• The event handler block must include “When BumperA is pressed”.

Which of the following statements below is true when creating a flowchart for an algorithm? Select all that apply.

• The arrows show the flow of the action.

• A command is represented by a rectangle.

• The beginning point is shown by a rectangle.

• The ending point is shown by a triangle.

What is the difference between a repeat loop and a forever loop?

• A forever loop repeats steps for a set number of times, whereas a repeat loop repeats steps until the program stops running.

• A repeat loop is used to copy and paste the same set of code, in order, and a forever loop is used if you want to copy and paste the same set of code in reverse order.

• A repeat loop repeats for a designated number of times, whereas a forever loop repeats until the program stops running.

• A forever loop is used to copy and paste the same set of code, in order, and a repeat loop is used if you want to copy and paste the same set of code in reverse order.

Drew, Anaya, and Olivia are working together on a gear train. They want the output speed to be faster than the input speed. How should they assemble the gears to achieve this result?

• The driving gear needs to be larger than the driven gear.

• The driving gear and driven gear need to be the same size.

• The output gear needs to be larger than the input gear.

• The driven gear needs to be larger than the driving gear.

You have been asked by a company to design a prototype for a propeller for their new drone. They want it to spin at a speed of at least 400 rpm. You are provided with the following materials: Gears in a variety of sizes A motor that spins at 200 rpm Describe the gear train that will meet the requirements.

• The number of rotations of the driving gear equals 5 and the number of rotations of the driven gear equals 1.

• The gear ratio of the driving gear and driven gear would be 1:1.

• There are 24 teeth on the input gear and 12 teeth on the output gear.

• There are 36 teeth on the input gear and 18 teeth on the output gear.