JAMB - Physics (1989 - No. 29)
An ammeter of resistance 1.0\(\Omega\) has a full-scale deflection of 50mA. Determine the resultant full-scale deflection of the meter when a shunt of 0.0111\(\Omega\) is connected across its terminals.
400mA
450mA
500mA
550mA
Paaiškinimas
V = 0.1 x 50 x 10-3 = 5 x 10-3volts
RT = \(\frac{0.1 \times 0.0111}{0.1 + 0.0111}\)
= 9.99 x 10-3\(\Omega\)
V = IR \(\Rightarrow\) I
= \(\frac{5 \times 10^{-3}}{9.9 \times 10^{-3}}\)
= 0.5A ; = 500mA
RT = \(\frac{0.1 \times 0.0111}{0.1 + 0.0111}\)
= 9.99 x 10-3\(\Omega\)
V = IR \(\Rightarrow\) I
= \(\frac{5 \times 10^{-3}}{9.9 \times 10^{-3}}\)
= 0.5A ; = 500mA