Question

The plate resistance of a triode is $3 \times 10^3 \Omega$ and its mutual conductance is $1.5 \times 10^{-3} A/V$. The amplification factor of the triode is

• A. $5 \times 10^{-5}$
• B. 4.5
• C. 45
• D. $2 \times 10^5$

Answer 1

The Correct Option is B

To find the amplification factor (denoted as μ) of a triode, we need to use the relationship between plate resistance (\(r_p\)), mutual conductance (\(g_m\)), and amplification factor. The relationship is given by the formula:

μ = r_p \cdot g_m

Where:

• \(r_p\) is the plate resistance
• \(g_m\) is the mutual conductance

Given:

• \(r_p = 3 \times 10^3 \, \Omega\)
• \(g_m = 1.5 \times 10^{-3} \, A/V\)

Substitute the values into the formula:

μ = (3 \times 10^3) \cdot (1.5 \times 10^{-3})

Perform the multiplication:

μ = 3 \cdot 1.5 \cdot (10^3 \cdot 10^{-3})

μ = 4.5 \cdot 10^{0}

μ = 4.5

Therefore, the amplification factor of the triode is 4.5, which matches the given correct option.

Thus, the correct answer is 4.5.