Karnataka SSLC 10th Science Question Paper 2026

The formula for power ($P$) is $P = \frac{1}{f}$ where $f$ is in meters. Given $P = +2D$, we have $2 = \frac{1}{f}$, which means $f = \frac{1}{2} = 0.5\text{ m}$. Thus, (a) is correct.

The best conductor is the material with the lowest electrical resistivity. Comparing the values: $1.60 \times 10^{-8} < 2.63 \times 10^{-8} < 5.20 \times 10^{-8} < 6.84 \times 10^{-8}$. Material M has the lowest resistivity, so it is the best conductor.

i) Rheostat: A rectangle with an arrow pointing to the top side or a zigzag line with an arrow crossing it. ii) Wire crossing without joining: Two lines crossing each other, where one line has a small semi-circular loop over the point of intersection.

The magnetic field produced by a circular coil is directly proportional to the number of turns ($n$). Therefore, a coil with 5 turns produces a magnetic field that is 5 times larger than that produced by a coil of 1 turn.

In the given circuit, the resistors A ($4\,\Omega$) and B ($20\,\Omega$) are connected in series. In a series combination, the current flowing through every component in the circuit is the same. Therefore, equal current flows through both resistors A and B.