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प्रश्न
Welders wear special goggles or face masks with glass windows to protect their eyes from electromagnetic radiations. Name the radiations and write the range of their frequency.
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उत्तर
Welders wear special goggles with glass windows to protect the eyes from Ultra Violet rays (UV rays). The range of UV rays is 4×10-7 m (400 nm) to 6×10-10 m (0.6 nm).
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संबंधित प्रश्न
Write some of the important uses of electromagnets.
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
Welders wear special glass goggles while working. Why? Explain.
Can a transformer work when it is connected to a D.C. source? Give a reason.
Complete the following diagram of a transformer and name the parts labeled A and B. Name the part you have drawn to complete the diagram . What is the material of this part? In this transformer a step-up or step-down? Why?
State the condition at which we say the two coils kept close to each other are perfectly coupled with each other.
Shown in the figure below is a metre bridge set up with null deflection in the galvanometer. The value of the unknown resistance R is ______
A 0.4 m wire, stretched horizontally, carries an electric current of 15 A, in a magnetic field whose magnetic field intensity is 0.1 N/Am. What is the magnitude of the wire?
In the given circuit, initially switch S1 is closed and S2 and S3 are open. After charging of capacitor, at t = 0, S1 is open and S2 and S3 are closed. If the relation between inductance capacitance and resistance is L = 4CR2 then the time (in sec) after which current passing through capacitor and inductor will be same is ______ × 10-4 N. (Given R = ℓn(2)mΩ, L = 2mH)
Which type of force is experienced by a moving charge in a magnetic field?
