Explanation

 A ray of light represents the direction of propagation of the wave.

A wavefront is a surface over which the phase of the wave is constant.

Rays are always perpendicular to the wavefronts.

Explanation

The series obtained by adding the terms of a geometric sequence is called a geometric series

Explanation

 CRIMINAL BEHAVIOR (جرائم پیشہ رویہ)

Crime (جرم)

Explanation

 If matrix A has an order of 3x2, then the order of its transpose (A') will be 2x3. 

Explanation

Among the halogen acids (HF, HCl, HBr, and HI), HI (hydroiodic acid) is the strongest.

The strength of an acid is determined by the ease with which it can donate a hydrogen ion (H+).

The H-I bond is the weakest of the halogen acid bonds, allowing HI to readily dissociate in water and release H+ ions. 

Explanation

The word "transistor" is derived from "transfer" and "resistor".

It signifies the transfer of resistance — specifically, it controls a large output resistance using a small input resistance.

In essence, a transistor transfers a signal from a low-resistance circuit to a high-resistance circuit, acting as an amplifier or switch.

Explanation

Shock absorbers in cars are designed to reduce the amplitude of vibrations (oscillations) after hitting a bump.

This is done by dissipating energy (usually through hydraulic or pneumatic damping).

The motion gradually dies out over time, which is characteristic of a damped oscillation.

Explanation

The matrix [a b c] is a row matrix.

A row matrix has only one row and can have multiple columns

Explanation

ax² − 2x + 2a = 0  

We are told: Sum of roots = Product of roots

Step 1: Use formulas  

For a quadratic equation ax² + bx + c = 0,  

- Sum of roots = −b/a

- Product of roots = c/a

So here:  

- Sum = −(−2)/a = 2/a  

- Product = (2a)/a = 2

Set them equal:  

2/a = 2

Multiply both sides by a:  

2 = 2a  

=> a = 1

Final Answer:  

a = 1

Explanation

In t-butyl alcohol, the tertiary carbon is bonded to no hydrogen atoms. 

A tertiary carbon is bonded to three other carbon atoms.

In t-butyl alcohol, the carbon with the OH group (the tertiary carbon

It is surrounded by three methyl groups, leaving no space for any hydrogen atoms to be attached directly to it.