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A student measures the thickness of a hu...

A student measures the thickness of a human hair by looking at it through a microscope of magnification 100. He makes 20 observations and findsd that the average width of the hair in the field of view of the microscope is 3.5mm. What is his estimate on the thickness of hair?

A

0.035mm

B

2mm

C

0.5mm

D

1.5mm

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KVPY PREVIOUS YEAR-MOCK TEST 6-EXERCISE
  1. Let P(r)=(Q)/(piR^4)r be the charge density distribution for a solid s...

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  2. A student measures the thickness of a human hair by looking at it thro...

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  3. A ray of light moving in air strikes at origin at grazing angle and th...

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  4. The eccentricity of the earth's orbit is 0.0167, the ratio of its maxi...

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  5. Two vessels A and B of different shapes have the same base area and ar...

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  6. When the diffraction pattern from a certain slit illuminated with lase...

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  7. What is the moment of inertia of a ring about a tangent to the periphe...

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  8. A particle moves with a velocity (3i+ 4j) m/s from origin.The displace...

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  9. Hydrogen (H), deuterium (D), singly ionized helium (He^(+)) and doubly...

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  10. The moment of inertia of a uniform thin rod of length L and mass M abo...

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  11. A charge q is uniformly distributed on a non-conducting disc of radius...

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  12. Refer to the common emitter amplifier circuit shown below, using a tra...

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  13. If the length of a tube is less and cannot accommodate the maximum ris...

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  14. A square wire loop with 2 m sides in perpendicular to a uniform magnet...

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  15. A car accelerates from rest at a constant rate alpha for some time, af...

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  16. Suppose Earth’s orbital motion around the Sun is suddenly stopped. Wha...

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  17. Four balls each of radius 10 cm and mass 1 kg,2 kg,3 kg and 4kg are at...

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  18. A particle of mass m moving with kinetic energy K, makes a head - on e...

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  19. One mole of an ideal monatomic gas has initial temperature T0, is made...

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  20. Let V and I be the readings of the voltmeter and the ammeter respectiv...

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