A conducting loop carrying a current I is placed in a uniform magnetic field pointing into the plane of the paper as shown. The loop will have a tendency to
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(a) Contract |
(b) Expand |
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(c) Move towards +ve x –axis |
(d) Move towards –ve x-axis |
(b) Expand
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Assertion : Bending a wire does not effect electrical resistance.
Reason : Resistance of wire is proportional to resistivity of material.
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(a) If both assertion and reason are true and the reason is the correct explanation of the assertion. |
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(b) If both assertion and reason are true but reason is not the correct explanation of the assertion. |
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(c) If assertion is true but reason is false. |
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(d) If the assertion and reason both are false. |
Consider the following statements A to B and identify the correct answer
A. Polarised light can be used to study the helical surface of nucleic acids.
B. Optics axis is a direction and not any particular line in the crystal
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(a) A and B are correct |
(b) A and B are wrong |
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(c) A is correct but B is wrong |
(d) A is wrong but B is correct |
Light of wavelength 4000 Å is incident on a sodium surface for which the threshold wave length of photo – electrons is 5420 Å. The work function of sodium is
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(a) 4.58 eV |
(b) 2.29 eV |
(c) 1.14 eV |
(d) 0.57 eV |
If the cathode–anode potential difference in an X-ray tube be 105 V, then the maximum energy of X-ray photon can be
| (a) 105 J | (b) 105 MeV | (c) 10–1 MeV | (d) 105 KeV |
For the myopic eye, the defect is cured by
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(a) Convex lens |
(b) Concave lens |
(c) Cylindrical lens |
(d) Toric lens |