Class 12th

This is a Multiple Choice Questions as classified in NCERT Exemplar

Answer- (d)

Explanation- when we increase temperature conductivity increases because number density is increasing after increasing temperature which decreases the relaxation time

The given system of equation can be written in the form of AK = B

Now,  = 3 * 1 - 2 * 2 = 3 - 4 = -1 ≠ 0.

∴ The system has unique solⁿ  and hence equation are consistent

Given, A is an invertible matrix of order 2.

∴ Option (B) is correct.

This is a  Short Answer Type Questions as classified in NCERT Exemplar

Explanation- power = 1W

Zener breakdown voltage = 5V

Minimum voltage = 3V

Maximum voltage = 7V

Current = power/voltage= 1/5=0.2A

The value of R for safe operation would be R = max voltage – Zener voltage/current

= 7- 5/0.2 = 2/0.2 = 10ohm

Kindly go through the solution

This is a  Short Answer Type Questions as classified in NCERT Exemplar

Explanation- this is AND GATE so truth table for this will be

Given, A= $\left[\begin{array}{cc}\hfill 1\hfill & \hfill 1\hfill \\ \hfill 1\hfill & \hfill 2\hfill & \hfill -3\hfill \\ \hfill 2\hfill & \hfill -1\hfill & \hfill 3\hfill \end{array}\right]$

This is a  Short Answer Type Questions as classified in NCERT Exemplar

Explanation- In elemental semiconductor, the band gap is such that the emission are in infrared region and not in visible region.

Kindly go through the solution

⇒ b = 1