Question
What is a filter circuit? Explain its functioning.
✓
Answer
→The rectified voltage is in the form of pulses of the shape of half sinusoilds. Though, it is unidirectional it does not have a steady value.
→To get steady dc output from pulsating voltage, the filter circuit is used. Filter circuits consist of only capacitor, only inductor or a combination of both. Since these additional circuits appear to filter out the ac ripple and give a pure dc voltage, so they are called filters.
• Functioning of a Filter Circuit :
→When the voltage across the capacitor is rising, it gets charged. If there is no external load, it remains charged to peak voltage of the rectified output.
→When there is a load, it gets discharged through the load and the voltage across it begins to fall. In the next half cycle of rectified output it again gets charged to the peak value.
→As shown in the fig., the rate of fall of the voltage across capacitor depends on the inverse product of capacitor C and the effective resistance $R_L$ used in the circuit and is called the time constant. To make the time constant large, value of C should be large. So capacitor input filters use large capacitors.
→The output voltage obtained by using capacitor input filter is nearer to the peak voltage of the rectified voltage.
→This type of filter is most widely used in power supplies.
→To get steady dc output from pulsating voltage, the filter circuit is used. Filter circuits consist of only capacitor, only inductor or a combination of both. Since these additional circuits appear to filter out the ac ripple and give a pure dc voltage, so they are called filters.
• Functioning of a Filter Circuit :
→When the voltage across the capacitor is rising, it gets charged. If there is no external load, it remains charged to peak voltage of the rectified output.
→When there is a load, it gets discharged through the load and the voltage across it begins to fall. In the next half cycle of rectified output it again gets charged to the peak value.
→As shown in the fig., the rate of fall of the voltage across capacitor depends on the inverse product of capacitor C and the effective resistance $R_L$ used in the circuit and is called the time constant. To make the time constant large, value of C should be large. So capacitor input filters use large capacitors.
→The output voltage obtained by using capacitor input filter is nearer to the peak voltage of the rectified voltage.
→This type of filter is most widely used in power supplies.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
More "2 Marks Questions" from SEMICONDUCTOR ELECTRONICS: MATERIALS, DEVICES AND SIMPLE CIRCUITS→SEMICONDUCTOR ELECTRONICS: MATERIALS, DEVICES AND SIMPLE CIRCUITS — all question types→Physics STD 12 Science question papers→Gujarat Board STD 12 Science question papers→Gujarat Board question paper generator→
Similar questions
A vertical rod is hit at one end. What kind of wave propagates in the rod if:
- The hit is made vertically.
- The hit is made horizontally?
Elemental semiconductor and compound semiconductors. Explain with examples.
Prove that $\varepsilon_0 \mu_0=\frac{1}{c^2}\left(\right.$ or $\left.c=\frac{1}{\sqrt{\varepsilon_0 \mu_0}}\right)$. ###
Derive the relation between the permittivity of free space $\left(\varepsilon_0\right)$, the permeability of free space $\left(\mu_0\right)$ and the speed of light $(c)$.
→Derive the relation between the permittivity of free space $\left(\varepsilon_0\right)$, the permeability of free space $\left(\mu_0\right)$ and the speed of light $(c)$.
Derive the formula of magnetic field for a current carrying infinite wire using Ampere's circuital law and discuss its interesting cases.
The force on a charged particle due to electric and magnetic fields is given by $\overrightarrow{\text{F}}=\text{q}\overrightarrow{\text{E}}+\text{q}\overrightarrow{\text{v}}\times\overrightarrow{\text{B}}.$ Suppose $\overrightarrow{\text{E}}$ is along the X-axis and $\overrightarrow{\text{B}}$ along the Y-axis. In what direction and with what minimum speed v should a positively charged particle be sent so that the net force on it is zero?
→What is the importance of radial magnetic field in a moving coil galvanometer?
The plates of a parallel-plate capacitor are made of circular discs of radii 5.0cm each. If the separation between the plates is 1.0mm, what is the capacitance?
An electric dipole of length I cm, which placed with its axis making an angle of $60^{\circ}$with uniform electric field, experiences a torque of $6\sqrt{3}$ Nm. Calculate the potential energy of the dipole if it has charge $\pm$ 2 nC.
→A plate of thickness t made of a material of refractive index $\mu$ is placed in front of one of the slits in a double slit experiment.
→- Find the change in the optical path due to introduction of the plate.
- What should be the minimum thickness t which will make the intensity at the centre of the fringe pattern zero? Wavelength of the light used is $\lambda$. Neglect any absorption of light in the plate.
Name the semiconductor device that can be used to regulate an unregulated dc power supply. With the help of I-V characteristics of this device, explain its working principle.