Rectification and smoothing

An ideal operational amplifier (op-amp) is described by infinite bandwidth and infinite slew rate. Explain what is meant by infinite bandwidth.

Feb/March 2018

The alternating power supply’s output p.d. is given by $V = 320\sin(100\pi t)$, where $V$ denotes the p.d. in volts and $t$ is measured in seconds.

Feb/March 2021

Fig. 7.1 presents the circuit diagram, which includes an operational amplifier (op-amp).

Feb/March 2021

Alternating current (a.c.) is changed to direct current (d.c.) by means of a full-wave rectification circuit. Figure 7.1 shows one section of this circuit diagram.

Feb/March 2022

A student has to design a circuit that will produce a direct voltage with peak value $9.0\,\text{V}$ from a $240\,\text{V}$ alternating supply. The student employs an ideal transformer and a bridge rectifier that contains four ideal diodes. Figure 6.1 shows the circuit diagram with part of it already completed.

May/June 2010

State the name of an electrical sensing device that reacts to a change in length.

May/June 2010

A student builds an electronic sensor intended to turn on a lamp whenever the light intensity is low. The circuit is partly shown in Fig. 10.1.

May/June 2012

A sinusoidal alternating voltage supply is connected to a bridge rectifier made up of four ideal diodes. The rectifier output is then connected to resistor $R$ and capacitor $C$, as shown in Fig. 6.1. The purpose of $C$ is to smooth the potential difference across $R$ to some extent. The graph in Fig. 6.2 shows how the potential difference $V$ across resistor $R$ varies with time $t$.

May/June 2012

An op-amp, or operational amplifier, can be included within the processing section of an electronic sensor.

May/June 2012

A student has designed an electronic sensor intended to turn on a lamp when the light intensity is low. A section of the circuit is shown in Fig. 10.1.

May/June 2012

A sinusoidal alternating-voltage source is linked to a bridge rectifier made of four ideal diodes. The rectifier output is then connected to resistor $R$ and capacitor $C$, as shown in Fig. 6.1. The purpose of $C$ is to smooth the potential difference across $R$ to some extent. Figure 6.2 shows how the potential difference $V$ across resistor $R$ varies with time $t$.

May/June 2012

State Faraday’s law for electromagnetic induction.

May/June 2013

Answer every question in the spaces provided.

May/June 2014

A bridge rectifier is made up of four ideal diodes A, B, C and D, as illustrated in Fig. 11.1. The rectifier’s output is joined to a load L with resistance $2.4\,\text{k}\Omega$.

May/June 2016

A bridge rectifier has four diodes. Its output is connected to a resistor R, as shown in Fig. 10.1. The e.m.f. input $E$ to the rectifier varies with time $t$ according to $E = 15\cos(210t)$ where $t$ is measured in seconds and $E$ is given in volts. Figure 10.2 shows how the potential difference $V$ across resistor R changes with time $t$. Determine:

May/June 2019

A bridge rectifier includes four diodes. Its output is linked to a resistor $R$, as illustrated in Fig. 10.1. The input e.m.f. $E$ supplied to the rectifier varies with time $t$ according to $E = 15\cos(210t)$, where $t$ is measured in seconds and $E$ in volts. Fig. 10.2 shows how the potential difference $V$ across resistor $R$ changes with time $t$.

May/June 2019

Fig. 5.1 displays four diodes together with a load resistor of resistance $1.2\,\text{k}\Omega$, arranged in a circuit used to rectify an alternating voltage.

May/June 2022

Fig. 5.1 contains four diodes and a load resistor with resistance $1.2\ \text{k}\Omega$, arranged in a circuit that is used to rectify an alternating voltage.

May/June 2022

Fig. 5.1 shows part of an electric circuit. The circuit is intended to give half-wave rectification of an alternating voltage with potential difference (p.d.) $V_{\text{IN}}$. The p.d. across the $14\,\text{k}\Omega$ resistor at the output is $V_{\text{OUT}}$.

May/June 2023

Within a bridge rectifier circuit, four diodes are arranged so that a sinusoidal a.c. input voltage $V_{\text{IN}}$ is rectified. Fig. 7.1 shows only part of the circuit, with three diodes omitted. The p.d. across the load resistor $R$ is the output p.d. $V_{\text{OUT}}$ of the bridge rectifier.

May/June 2023

A section of an electric circuit is shown in Fig. 5.1. This circuit is used to obtain half-wave rectification of an alternating voltage with potential difference (p.d.) $V_{\text{IN}}$. The output p.d. across the $14\,\text{k}\Omega$ resistor is $V_{\text{OUT}}$.

May/June 2023

Fig. 6.1 illustrates a circuit that rectifies an alternating input voltage $V_{IN}$ and gives an output voltage $V_{OUT}$ across a resistor $R$. The rectification circuit has four terminals named W, X, Y and Z. A capacitor $C$ is placed in parallel with resistor $R$.

May/June 2025

Fig. 8.1 illustrates a circuit that converts an alternating input voltage into a rectified output. The input voltage $V_{IN}$ is sinusoidal, and the rectified output voltage $V_{OUT}$ is across resistor $R$. In Fig. 8.2, the variation of $V_{IN}$ with time $t$ has amplitude $V_0$ and period $T$. The root-mean-square (r.m.s.) value of $V_{IN}$ is $6.0\,\text{V}$.

May/June 2025

Fig. 6.1 presents a circuit that converts an alternating input voltage $V_{IN}$ into an output voltage $V_{OUT}$ across a resistor $R$. The rectification circuit has four terminals named W, X, Y and Z. A capacitor $C$ is joined in parallel with resistor $R$.

May/June 2025

State three characteristics of an ideal operational amplifier (op-amp).

Oct/Nov 2010

Fig. 5.1 shows the components used for a bridge rectifier.

Oct/Nov 2011

Figure 6.1 shows a bridge rectifier built from four ideal diodes A, B, C and D arranged as drawn. An alternating supply is connected across terminals X and Y.

Oct/Nov 2012

A student creates an electronic sensor to check whether the temperature inside a refrigerator is higher or lower than a chosen value. The circuit appears in Fig. 9.1.

Oct/Nov 2012

An ideal operational amplifier (op-amp) is described as having an infinite slew rate. Explain what infinite slew rate means.

Oct/Nov 2016

Fig. 11.1 shows the circuit of a full-wave rectifier built from four ideal diodes. A resistor $R$ is connected across the output $AB$ of the rectifier.

Oct/Nov 2017

Fig. 10.1 shows a bridge rectifier made from four ideal diodes. A sinusoidal alternating electromotive force (e.m.f.) is applied between points A and B, and its root-mean-square (r.m.s.) value is $7.0\,\text{V}$.

Oct/Nov 2019

Fig. 10.1 shows a bridge rectifier made with four ideal diodes. The sinusoidal alternating electromotive force (e.m.f.) applied across points A and B has a root-mean-square (r.m.s.) value of $7.0\ \text{V}$.

Oct/Nov 2019

An ideal operational amplifier (op-amp) is characterised by infinite bandwidth and zero output impedance.

Oct/Nov 2019

State two characteristics of an ideal operational amplifier (op-amp).

Oct/Nov 2021

State the meaning of rectification when applied to an alternating voltage.

Oct/Nov 2024

State what rectification of an alternating voltage means.

Oct/Nov 2024

Fig. 6.1 depicts part of a bridge rectifier circuit that may be used to rectify an alternating input voltage $V_{\mathrm{IN}}$. Four diodes are present in the circuit, and one is drawn. The rectified output voltage $V_{\mathrm{OUT}}$ is applied across load resistor $R$.

Oct/Nov 2025