Question Detail

PHY 104 Oscillatory Motion Objective Question

Question

If the displacement of a moving particle is given by x = 5cos ωt + 12sin ωt, what is the amplitude of the motion?
Options
A 5 units
B 12 units
C 13 units
Correct Answer
D 17 units
Correct Answer

Option C is the correct answer.

Detailed Explanation

From Worked Example 42 (page 44) or the 'Alternative Mathematical Expressions for SHM' section (page 3, Equation 6), if x(t) = C cos ωt + D sin ωt, then the amplitude A is given by A = √(C² + D²). Here, C = 5 and D = 12. So, A = √(5² + 12²) = √(25 + 144) = √169 = 13 units.

Hint

Recall the formula for amplitude when the SHM equation is expressed as a sum of sine and cosine functions. Refer to the 'Generalized Mathematical Expressions for SHM' or 'Alternative Mathematical Expressions for SHM' section on pages 2-3.

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