Explanation

At terminal velocity, the viscous drag balances the weight of the body.

Net force = Weight – Drag = 0 → no acceleration, constant velocity.

Explanation

Magnetic flux: Φ = B × A × cosθ

First loop: Φ = 0.5 × 1 × cos0° = 0.5 Wb → Second loop: 0.5 × B × cos0° = 0.5 → B = 1.0 T

Explanation

Magnetic force is given by F = q(v × B), perpendicular to both velocity v and magnetic field B.

Electron moves along x-axis, B is in xz-plane → v × B points along y-axis.

Explanation

The penetration power of the X-rays depends  on the wavelength and frequency of X-rays

The penetration power of the X-rays will be more when the energy of the X-ray is more.

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Related Question:

Explanation

Radio waves can travel long distances through space without much interference.

They are widely used in space communication and satellite transmissions.

Explanation

From vector relations= |A × B| = AB sinθ and A.B = AB cosθ.

Dividing them gives tanθ = |A × B|/A.B.

Explanation

Explanation

Efficiency n = Output Power/Input Power × 100.

If output power is half of input power, n = 1/2 × 100 = 50%.

Explanation

Negative sign shows decrease in speed (retardation).

Magnitude of angular retardation = π rad/s².

Explanation

At the speed of light, time dilation becomes infinite according to Einstein’s relativity.

This means the moving observer would see the clock as if time has stopped.