A galvanometer acting as a voltmeter should have:
1. low resistance in series with its coil
2. low resistance in parallel with its coil
3. high resistance in series with its coil
4. high resistance in parallel with its coil
 

Subtopic:  Moving Coil Galvanometer |
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The equivalent resistance across \(A\) and \(B\) is: 
     
1. \(2~\Omega\)
2. \(3~\Omega\)
3. \(4~\Omega\)
4. \(5~\Omega\)
Subtopic:  Wheatstone Bridge |
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A black body has a wavelength of \(\lambda\) at temperature \(2000\) K. Its corresponding wavelength at temperature \(3000\) K will be:
1. \(\frac{2\lambda}{3}\)
2. \(\frac{3\lambda}{2}\)
3. \(\frac{4\lambda}{9}\)
4. \(\frac{9\lambda}{4}\)

 

Subtopic:  Wien's Displacement Law |
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At room temperature, copper has free electron density of \(8.4 \times 10^{28}\) m-3. The electron drift velocity in a copper conductor of a cross-sectional area of \(10^{-6}\) m2 and carrying a current of \(5.4\) A, will be:
1. \(4\) ms-1
2. \(0.4\) ms-1
3. \(4\) cms-1
4. \(0.4\) mms-1

Subtopic:  Current & Current Density |
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A uniform wire of resistance \(R\) and length \(L\) is cut into four equal parts, each of length \(L/4\) which is then connected in parallel combination. The effective resistance of the combination will be:
1. \(R\)
2. \(4R\)
3. \(\frac R4\)
4. \(\frac{R}{16}\)

 

Subtopic:  Combination of Resistors |
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The half-life of a radioisotope is \(4\) h. If the initial mass of the isotope was \(200\) g, then the mass remaining after \(24\) h will be:
1. \(1.042\) g
2. \(2.084\) g
3. \(3.125\) g
4. \(4.167\) g

Subtopic:  Radioactivity (OLD NCERT) |
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Which logic gate is represented by the following combination of logic gates? 
    
1. OR
2. AND
3. NAND
4. None of these

Subtopic:  Logic gates |
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The work function for metals \(A,B\) and \(C\) are respectively \(1.22~\mathrm{eV}\), \(2.0~\mathrm{eV}\) and \(5~\mathrm{eV}\). According to Einstein’s equation, the metals that will emit photoelectrons for radiation of wavelength \(410~\mathrm{\mathring A}\) is/are:
1. none
2. A only
3. A and B only
4. A and B only

Subtopic:  Einstein's Photoelectric Equation |
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Two boys are standing at the ends \(A\) and \(B\) of a ground, where \(AB = a.\) The boy at \(B\) starts running in a direction perpendicular to \(AB\) with velocity \(v_1.\) The boy \(A\) starts running simultaneously with velocity \(v\) and catches the other boy in a time \(t,\) where \(t\) is:
1. \(\frac{a}{\sqrt{v^2+v_1~^2}}\)
2. \(\sqrt{\frac{a^2}{v^2-v_1~^2}}\)
3. \(\frac{a}{(v-v_1)}\)
4. \(\frac{a}{(v+v_1)}\)

Subtopic:  Relative Motion |
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A \(5\) amp fuse wire can withstand a maximum power of \(1\) W in circuit. The resistance of the fuse wire is:
1. \(0.2\) Ω
2. \(5\) Ω
3. \(0.4\) Ω
4. \(0.04\) Ω

Subtopic:  Heating Effects of Current |
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