Problem 57-1    Source:   Problem elaborated by the author of the site.

At the input of a circuit, a sinusoidal signal of 1.0 Vrms was applied and at the output of the circuit a signal with an intensity of 2.0 Vrms was measured. Calculate, in dB, whether there was gain or loss of the signal.

Problem 57-2    Source:   Problem elaborated by the author of the site.

At the input of a resistive network, a sinusoidal signal with 10 watts of the power was injected and at the output, a power of 3 watts was measured on the load. Calculate the loss of power caused by the resistive network.

Problem 57-3    Source:   Problem elaborated by the author of the site.

The resistive network shown in the Figure 57-3.1, feeds a resistive load (not shown in the figure) and the following values were measured:   V_i = 10.0 V , V_o = 4.50 V , I_i = 8.0 A and I₀ = 5.0 A. Make an evaluation of gains or losses related to power, voltage and current in the network.

Problem 57-4    Source:   Problem elaborated by the author of the site.

Assuming a speaker as a point source and emitting a power of 10 W, calculate the sound pressure to 1 meter and 10 meters away from it.

Problem 57-5    Source:   Problem prepared by the author of the site.

Assume an amplifier with a midband gain of A_vm = 400 and with a frequency response given by f₁ = 40 Hz and f₂ = 16,000 Hz. Calculate the gain of this amplifier in the frequencies of 20 Hz and 20,000 Hz.

Problem 57-6    Source:   Problem prepared by the author of the site.

The technical manual of an RF amplifier recommends that the amplifier should not work with an output power greater than 33 dBm. What power is that in mW and in W?