Question

In ohm's law exp., reading of voltmeter across the resistor is 12.5 V and reading of current i = 0.20 Amp. Estimate the resistance in correct significant figure.

• A. 62 ohm
• B. 31 ohm
• C. 63 ohm
• D. 60 ohm

Answer 1

The correct option is A 62 ohm

Given : $V=12.5$ volts $i=0.20Amp$

Resistance $R=\frac{V}{i}$

$⟹R=\frac{12.5}{0.20}=62.5\Omega$

Since, $12.5$ has 3 significant figures and $0.20$ has 2 significant figure.

So, the answer must contain only 2 significant figures.

$⟹R=62\Omega$