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A particle oscillates along the x-axis according to the law, mathrmx(t) = mathrmx_0 sin^2left(fract2 ight) where x_0 = 1 \, m . The kinetic energy (K) of the particle as a function of x is correctly represented by the graph.

Solution & Explanation

### Related Formula x(t) = x_0 sin^2left(fract2 ight) = x_0 left(frac1 - cos t2 ight) ### Core Logic Given x_0 = 1\ mathrmm, the position simplifies to: x = frac1 - cos t2 implies 2x - 1 = -cos t implies cos t = 1 - 2x Differentiating x(t) to find velocity v: v = fracdxdt = frac12sin t Kinetic energy K is proportional to v^2: K = frac12mv^2 = frac12m left(frac14sin^2 t ight) = fracm8(1 - cos^2 t) Substituting cos t = 1 - 2x: K = fracm8left[1 - (1 - 2x)^2 ight] = fracm8left[1 - (1 - 4x + 4x^2) ight] = fracm8(4x - 4x^2) = fracm2(x - x^2) This is an inverted parabola (K propto x - x^2) passing through x=0 and x=1, reaching a peak at x = 1/2. This matches Graph (1). ### Pattern Recognition The position oscillates purely within the boundary interval [0, 1]. Kinetic energy peaks perfectly at the equilibrium midpoint x = 1/2 where speed is maximum. ### Evaluation Rubric / Model Answer null ### Chapter Mix Class 11 Physics: Oscillations

Reference Study Guides

More Oscillations Previous-Year Questions — Page 2

Q5 2025 Simple Pendulum
Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : Time period of a simple pendulum is longer at the top of a mountain than that at the base of the mountain. [cite: 1, 5] Reason (R) : Time period of a simple pendulum decreases with increasing value of acceleration due to gravity and vice-versa. [cite: 1, 5] In the light of the above statements, choose the most appropriate answer from the options given below:
  • A. textBoth (A) and (R) are true but (R) is not the correct explanation of (A).
  • B. textBoth (A) and (R) are true and (R) is the correct explanation of (A).
  • C. text(A) is true but (R) is false.
  • D. text(A) is false but (R) is true.

Solution

### Related Formula T = 2pisqrtfraclg ### Core Logic As altitude h increases at the top of a mountain, acceleration due to gravity g drops down according to [cite: 634, 635]: g = fracg_0 R^2(R+h)^2 Since T propto frac1sqrtg, a decreased g directly makes the time period T longer[cite: 634, 635]. ### Pattern Recognition Higher altitude implies smaller gravity field implies slower pendulum oscillations implies longer period[cite: 634, 635]. ### Chapter Mix Class 11 Physics: Oscillations Class 11 Physics: Gravitation

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