All-in-One Exam Prep Platform

Explanation

Optical fibers transmit data as light signals.

The signal is confined within the fiber due to the phenomenon where light hits a medium boundary.

It is completely reflected back.

Explanation

Elastic means لچکدار

Rigid means غیر لچکدار

Explanation

Explanation

Explanation

Explanation

Explanation

Using the Heisenberg Uncertainty Principle:

ΔE * Δt >= h/4π

where ΔE = h * Δv (energy uncertainty) and Δt = 10^(-8) s (lifetime)

h * Δv * 10^(-8) >= h/4π

Δv >= 1/(4π * 10^(-8))

≈ 8 x 10^6 Hz

Explanation

Explanation

Using the Parallel Axis Theorem:

I = I_CM + Md^2

where I_CM = MR^2/2 and d = R (radius)

I = MR^2/2 + MR^2

= 3/2 MR^2

Explanation

When a spherical ball rolls without slipping:

Total energy (E) = Kinetic energy (K) + Rotational energy (U)

K = (1/2)mv^2

U = (1/2)Iω^2 = (1/5)mv^2 (for a sphere)

E = K + U = (1/2)mv^2 + (1/5)mv^2 = (7/10)mv^2

Fraction of energy associated with rotation:

U/E = ((1/5)mv^2) / ((7/10)mv^2) = 2/7