COMEDK 2024 MORNING SHIFT

A \(500 \mathrm{~W}\) heating unit is designed to operate on a \(400 \mathrm{~V}\) line. If line voltage drops to \(160 \mathrm{~V}\), the percentage drop in heat output will be:

$$\text { If } x, y, z \text { are non zero real numbers, then inverse of matrix } A=\left[\begin{array}{lll} x & 0 & 0 \\ 0 & y & 0 \\ 0 & 0 & z \end{array}\right] \text { is }$$

Which one of the following shows the correct increasing order of basic nature of the given compounds?

A: Phenylmethanamine

B: N-Ethylethanamine

C:N, N-Dimethylaniline

D : N, N-Dimethylmethanamine

A cell of emf E and internal resistance r is connected to two external resistances \(\mathrm{R_1}\) and \(\mathrm{R_2}\) and a perfect ammeter. The current in the circuit is measured in four different situations:

(a) without any external resistance in the circuit.

(b) with resistance \(\mathrm{R_1}\) only

(c) with \(\mathrm{R_1}\) and \(\mathrm{R_2}\) in series combination.

(d) with \(\mathrm{R_1}\) and \(\mathrm{R_2}\) in parallel combination.

The currents measured in the four cases in ascending order are

If \(\left[\begin{array}{lll} 1 & x & 1 \[\end{array}\right]\left[\begin{array}{ccc}\] 1 & 3 & 2 \\ 2 & 5 & 1 \\ 15 & 3 & 2 \[\end{array}\right]\left[\begin{array}{l}\] 1 \\ 2 \\ x \[\end{array}\right]=[0]\) then x is equal to\]

A given mass of a hydrocarbon on complete combustion produced \(176 \mathrm{~g}\) of \(\mathrm{CO}_2\) and \(90 \mathrm{~g}\) of \(\mathrm{H}_2 \mathrm{O}\). What is the Molecular formula of the compound?