Question

Assertion $x=A\cos \omega t$ represents a periodic function. The value of $x$ varies between $+A$ and $-A$.
Reason Amplitude is a vector quantity.

• A. Both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
• B. Both Assertion and Reason are correct but Reason is not the correct explanation of Assertion.
• C. Assertion is correct but Reason is incorrect.
• D. Assertion is incorrect but Reason is correct.

Answer 1

Answer: (C)

In $x=A\cos \omega t$, since $\cos \omega t$ varies between $+1$ to $-1$, thus the value of $x$ varies between $+A$ and $-A$.
Amplitude $A$ is a scalar quantity.
Therefore, Assertion is correct but Reason is incorrect.