C++ | MCQs

Explanation

The SI unit of conductance is the Siemens (S).

It is the reciprocal of resistance, which is measured in ohms (Ω).

Therefore, 1 Siemens is equal to 1/ohm.

The term "mho" is also sometimes used as a unit of conductance, but Siemens is the standard SI unit. 

Explanation

The efficiency of a Carnot engine is defined as the ratio of the heat absorbed from the hot reservoir (heat accepted) to the heat rejected to the cold reservoir (heat rejected).

This efficiency is directly related to the temperature difference between the two reservoirs. 

Explanation

The fine ruling (track spacing) on a CD is about 0.5 micrometers (µm).

This microscopic spacing allows the CD to store large amounts of data through optical encoding.

Explanation

A P-N junction is the basic structure of a diode, and how it conducts current depends on how it's connected:

Forward bias:

The positive terminal of the battery is connected to the P-side, and the negative terminal to the N-side.

This reduces the potential barrier, allowing current to flow through the junction.

Explanation

• Energy
• Momentum
• Charge

Explanation

In a metallic conductor, current flows due to the movement of free electrons in the conduction band.

These electrons drift under the influence of an electric field, creating electric current.

Explanation

Given:

• Radius of the circle$r=4$ meters

• Arc length (distance along the circumference), $s=14$ meters

We are to find the displacement, which is the straight-line distance between the starting and ending points of the arc.

Step 1: Find the angle subtended by the arc at the center (θ in radians):

$$theta = frac{s}{r} = frac{14}{4} = 3.5 , text{radians}$$

Step 2: Use the chord length formula to find displacement:

Displacement=2rsin(θ/2​)
=2×4×sin(3.5/2​)=8×sin(1.75)
sin(1.75radians)≈0.983
$$\text{Displacement}\approx 8\times 0.983\approx 7.864\text{meters}$$

Explanation

Atto (a) = 10⁻¹⁸

Femto (f) = 10⁻¹⁵

Nano (n) = 10⁻⁹

Peta (P) = 10¹⁵

So, Atto has the smallest (lowest) value.

Explanation

To find the energy stored in a capacitor, we use the formula:

E=1/2​CV^2

Where:

• $\mathrm{<br>}$

• $V=100\text{V}$

Calculation:

$$E = frac{1}{2} times 4 times 10^{-6} times (100)^2$$E=1/2​×4×10^−6×10000
E=2×10^−6×10000

$$=0.02\text{J}$$

Explanation

Cloud formation typically occurs in the atmosphere under constant pressure conditions, meaning it is an isobaric process