Question

does the length of the pendulum affect the period of the pendulum?
identifying components of cer
use the following information to answer the question about claim, evidence, and reasoning.

experiment:
a period can be thought of as the length of time required to complete one swing of a pendulum.

four pendulums with different lengths of string, but the same mass, are dropped from the same angle. the number of swings in 30 seconds is measured for each pendulum.

data table:
length (m) | swings (in 30 sec)
0.2 | 28

which of the following would be a reasoning statement for a cer?

• pendulum periods are like waves; the length of string affects the period time.
• pendulum periods are like waves; length should have no affect on it.
• pendulum periods are like waves; only mass will affect it.

Explanation:

Identify the definition of a reasoning statement in CER

A reasoning statement connects the evidence to the claim using scientific principles or theories.

Analyze the given options

• Option 1: "Pendulum periods are like waves; the length of string affects the period time." This connects the physical concept of waves/pendulums (scientific principle) to how length affects the period.
• Option 2: "Pendulum periods are like waves; length should have no affect on it." This statement contains a grammatical error ("affect" instead of "effect") and is scientifically incorrect based on the experiment.
• Option 3: "Pendulum periods are like waves; only mass will affect it." This is scientifically incorrect as mass does not affect the period of a simple pendulum.

Select the best reasoning statement

Option 1 correctly uses a scientific analogy ("like waves") to explain the relationship between string length and period.

Answer:

• (A) Pendulum periods are like waves; the length of string affects the period time. (Correct answer)
• (B) Pendulum periods are like waves; length should have no affect on it
• (C) Pendulum periods are like waves; only mass will affect it