Explanation

If the frequency of incident radiation in the photoelectric effect is increased beyond the threshold frequency, it will not affect the photoelectric current. 

Explanation

In simple harmonic motion (S.H.M), the restoring force is minimum at Mean position. 

The restoring force is directly proportional to the displacement from the mean position.

At the mean position, the displacement is zero, meaning the restoring force is also zero at that point. 

Explanation

Lenses form images through Refraction.

It bends light to focus it on a point, creating an image.

Explanation

If the speed of a moving particle increases, the wavelength associated with it will decrease. 

This is due to the relationship between wavelength and momentum in the de Broglie equation, where wavelength is inversely proportional to velocity. 

Explanation

A solar eclipse occurs when the Moon passes between Earth and the Sun,

thereby obscuring the view of the Sun from a small part of the Earth, totally or partially.

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Explanation

A typical diffraction grating can have 400 to 50,000 lines per centimeter, depending on precision and application.

Higher line densities provide better spectral resolution for analyzing light.

Explanation

If a vector is given as →A = xi, its magnitude is simply |→A| = √(x²) = x (assuming x ≥ 0).

Explanation

 T = 2π√(L/g)

= 2π√(1/9.8)

≈ 2.006 s

Explanation

The signal from a remote control to the device operated by it travels at the speed of Light. 

Explanation

 A · A = |A||A|cos(0) = A² (since cos 0 = 1)  

   - This gives the magnitude squared of the vector.