Advertisements
Advertisements
प्रश्न
L, C and R represent the physical quantities inductance, capacitance and resistance respectively. Which of the following combinations have dimensions of frequency?
(a) `1/(RC)`
(b) `R/L`
(c) `1/sqrt(LC)`
(d) C/L
Advertisements
उत्तर
(a) `1/(RC)`
(b) `R/L`
(c) `1/sqrt(LC)`
The time constant of the RC circuit is given by
`tau=RC`
On taking the reciprocal of the above relation, we get
`f_1=1/(RC).............(1)`
f1 will have the dimensions of the frequency.
The time constant of the LR circuit is given by
`tau=L/R`
On taking the reciprocal of the above relation, we get
`f_2=R/L............(2)`
f2 will have the dimensions of the frequency.
On multiplying eq. (1) and (2), we get
`f_1f_2=1/(LC)`
`rArrsqrt(f_1f_2)=1/sqrt(LC)`
Thus, `sqrt(f_1f_2)` will have the dimensions of the frequency.
APPEARS IN
संबंधित प्रश्न
Two circular coils A and B are placed closed to each other. If the current in the coil A is changed, will some current be induced in the coil B? Give reason.
A rectangular wire loop of sides 8 cm and 2 cm with a small cut is moving out of a region of uniform magnetic field of magnitude 0.3 T directed normal to the loop. What is the emf developed across the cut if the velocity of the loop is 1 cm s−1 in a direction normal to the
- longer side,
- shorter side of the loop?
For how long does the induced voltage last in each case?
Prove theoretically (electromagnetic induction) `e = (dphi)/(dt)`
The direction of current in the coil at one end of an electromagnet is clockwise. This end of the electromagnet will be:
(a) north pole
(b) east pole
(c) south pole
(d) west pole
What do you understand by the term "electromagnetic induction"? Explain with the help of a diagram.
Name one device which works on the phenomenon of electromagnetic induction.
In which of the following case does the electromagnetic induction occur?
The current is stopped in a wire held near a loop of wire .
When Puja, a student of 10th class, watched her mother washing clothes in the open, she observed coloured soap bubbles and was curious to know why the soap bubbles appear coloured. In the evening when her father, an engineer by profession, came home, she asked him this question. Her father explained to her the basic phenomenon of physics due to which the soap bubbles appear coloured.
(a) What according to you are the values displayed by Puja and her father?
(b) State the phenomenon of light involved in the formation of coloured soap bubbles.
Consider the energy density in a solenoid at its centre and that near its ends. Which of the two is greater?
Draw a simple labeled diagram of a step-up transformer.
A coil has a self-inductance of 0·05 Henry. Find the magnitude of the emf induced in it when the current flowing through it is changing at the rate of 100 As-1.
State the purpose of soft iron core used in making an electromagnet.
For making a strong electromagnet the material of the core should be ______.
Sea turtles return to their birth beach many decades after they were born due to ______.
A coil of one turn is made of a wire of certain length and then from the same length, a coil of two turns is made. If the same current is passed in both the cases, then the ratio of the magnetic inductions at their centres will be:
The working of a dynamo is based on the principle of
The charge will flow through a galvanometer of resistance 200Ω connected to a 400Ω circular coil of 1000 turns wound on a wooden stick 20 mm in diameter, if a magnetic field B = 0.012 T parallel to the axis of the stick decreased suddenly to zero, is near ______.
Which type of force is experienced by a moving charge in a magnetic field?
When an electric current is passed through a wire or a coil, a magnetic field is produced. Is the reverse phenomenon possible i.e, can a magnetic field produce an electric current? Explain with the help of an appropriate example.
