Tag: physics
Questions Related to physics
Sunspots on the photosphere are due to.
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Eclipses caused by planets
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Comparatively cooler regions
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Granulation's
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Cloudy weather on the earth
Sunspots are temporary phenomenon on the sun photosphere that appears as spots darker than the surrounding area.
The reason for enormous energy output of the sun is.
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Combustion of hydrogen
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Formation of helium
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Thermo nuclear fusing reaction
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Electromagnetic field.
Reason for enormous energy output of sun is the fusion reaction
Which resistor is difficult to make of having a value less than about 2 Ohms?
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Iron Resistor
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Carbon Resistor
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Wire wound Resistor
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Both b and c
Carbon resistor is difficult to make of having a value less than about $20 $Ohms because they have ability to withstand high energy pulses, when current flow through the carbon composition body conducts the energy . So carbon resistor can be made with a higher resistance
Resistors are generally colour coded to:
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Indicate the type of the circuit in which they are to be used
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Identify whether they are ohmic or non-ohmic
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Determine their values in ohm
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Determine whether they are wire wound or composition resistors
Components and wires are coded with colors to identify their value and function. The colors brown, red, green, blue, and violet are used as tolerance codes on 5-band resistors only.
Which of the following is not true for wire wound resistor?
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It has a lower order of stability and reliability.
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It has high power rating with a low tolerance value.
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Easy to make wire wound resistor of value 0.01 Ohm.
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It is not suitable for high-frequency circuits.
A given resistor has the following colour scheme of the various strips on it : Brown, black, green and silver. Its value in ohm is :
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$1.0 \times 10^4 \pm 10\%$
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$1.0 \times 10^5 \pm 10\%$
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$1.0 \times 10^6 \pm 10\%$
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$1.0 \times 10^7 \pm 10\%$
Numbers attached for brown, black, green and silver are $1, 0, 5, \pm10\%$. Therefore the resistance of given resistor
$= 10 \times 10^5\ \Omega \pm 10\%$.
Which of the following is not the disadvantage of wire wound resistor?
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It has a big size which is not suitable for many of the applications.
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It has high power rating with a low tolerance value.
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Resistance value gets changed by a change in temperature, humidity etc.
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It is not suitable for high-frequency circuits.
In wired resistors are mainly produced with alloys, since pure metal has a high temperature co-efficient.
There are three red colored bands on a carbon resistor. What is its resistance ?
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$2.2$
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$2200$
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$\left( 2200\pm 20\% \right) $
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$1.76$ to $2.64$
According to the color code of resistance,
Which color band in the color coding of a resistor has the tolerance $\pm2$%?
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Orange
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Black
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Silver
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Red
Red color band in the color coding of a resistor has the tolerance of $\pm2\%$
Carbon resistors are of two types :
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composition type resistor and film type resistor
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rheostat and film type resistor
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rheostat and variable resistor
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composition type resistor and rheostat