MT4-3 Ro2 1718

How do if-else statements work?

• The robot checks the condition next to the keyword if. If the condition is true, the commands that belong to the "if" are run. If the condition is false, the commands that belong to the "else" are run.

• The robot checks the condition next to the keyword if. If the condition is true, the commands that belong to the "if" are run and the robot loops back to check again. If the condition is false, the commands that belong to the "else" are run.

• The robot checks the condition next to the keyword if. If the condition is true, the commands that belong to the "if" are run for the duration of the program. If the condition is false, the commands that belong to the "else" are run for the duration of the program.

How many times does an If statement run its code (if the condition is true)?

• Once

• None

• Twice

• As long as the condition is true

In an if-else statement, the else branch:

• Will never be run.

• Will always run after the if statement.

• Will run if the if statement is false.

• Repeats forever.

Ambient sources of light such as the sun and lamps can affect Line Tracking sensor readings and the appropriate thresholds for them.

• True

• False

• Only if the lamps are incandescent

• Only if the lamps are phosphorescent

Why is the VEX Light Sensor considered a Passive sensor, while the VEX Line Tracking Sensor is considered an Active sensor?

• The Line Tracking Sensor is more commonly found on highly-mobile robots; the Light Sensor is not.

• The Line Tracking Sensor has its own IR light source; the Light Sensor does not.

• The Line Tracking Sensor is not affected by ambient light; the Light Sensor is affected by ambient light.

On the VEX Cortex, what range of values do the Line Tracking Sensors provide?

• 0 to 100

• 0 to 1023

• 0 to 4095

• -127 to 127

What is a Threshold in robot programming?

• A threshold is a minimal motor power level before the motors will start to spin.

• A threshold is a safe starting zone for your robot, ensuring it won't fall off a challenge table.

• A threshold is a value that separates many values into just two categories so the robot can make a decision

When line tracking, if the robot consistently swings past the line or doesn't move at all, it may be a problem with:

• the ROBOTC Sensor Debug Window.

• the name of your program.

• the threshold value.

• the robot's memory being corrupt.

To change how long a robot tracks a line, you generally would modify the:

• While loop condition

• Threshold value

• Motor power levels

When using the VEX Line Tracker sensor, a dark surface gives a:

• Value of 1

• High Sensor Value

• Value of 0

• Low Sensor Value