A Controlled Experiment Is One in Which

question 10

Multiple Choice

A controlled experiment is one in which

• A) the experiment is repeated many times to ensure that the results are accurate.
• B) the experiment proceeds at a slow pace to guarantee that the scientist can carefully observe all reactions and process all experimental data.
• C) there are at least two groups, one of which does not receive the experimental treatment.
• D) there are at least two groups, one differing from the other by two or more variables.

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Definitions:

PLC

Programmable Logic Controller, a digital computer used for automation of industrial processes, such as control of machinery or factory assembly lines.

Timing Circuit

An electronic circuit designed to produce specific time delays or to trigger events at precise intervals.

Cascading

In the programming of timers and counters, a technique used to extend the timing or counting range beyond what would normally be available. This technique involves the driving of one timer or counter instruction from the output of another, similar instruction.

Timers

Devices or software tools that measure time intervals, commonly used in industrial control systems to control operations and processes over time.