PHY192: Introductory Physics Practical Ii TMA3

$ and the driver cell has an emf of 2.00 V. What is the value of the resistance R if a balance point is obtained at 0.60 m along PQ when measuring an emf of 6.00mV?

 $495\Omega$

 $995\Omega$

 $195\Omega$

 $95\Omega$

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Question 3 : The lens of the human eye is

 converging

 diverging

 concave

 planconcave

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Question 4 : In an experiment, potential difference is plotted on the vertical axis and current on the horizontal axis. The slope of the graph represents

 conductivity

 conductance

 resistivity

 resistance

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Question 5 : Diopter measures

 linear magnification of lens

 inverse of object distance from lens

 power of lens

 inverse of image distnce from lens

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Question 6 : The null condition in potentiometer experiment shows that

 potential differences are varying in the circuit

 the potential difference under test is zero

 potential difference are balanced

 current is varying in the circuit

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Question 7 : In an experiment with a concave mirror, the image of an optical pin which is 4 times its size was cast on on a screen 6m from the object pin. How far from the object pin should the mirror be placed?

 3m

 6m

 2m

 8m

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Question 8 : The image of an object which is between the concave mirror’s reflecting surface and its principal focus is

 in front of the mirror erect virtual and enlarged

 behind the mirror erect virtual and enlarged

 behind the mirror inverted real and diminished

 in front of the mirror erect real and diminished

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Question 9 : In an experiment to determine the focal length of a convex lens, 1/u $\left(c{m}^{-1}\right)$ was plotted on horizontal and 1/v $\left(c{m}^{-1}\right)$ on the vertical axis, where u and v have their usual meaning. What is the physical significance of the reciprocal of the intercept on the horizontal axis?

 linear magnification

 focal length

 image distance

 object distance

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Question 10 : In practical experiment inloving the use of optical pins, parallax is reduced or removed if on slightly displacing one’s eye from side to side

 the object and image move in opposite directions relative to each other

 the object and image are not coincident but move together in same directions

 the object and image are coincident and move together in the same direction

 the object and image are coincident and remain stationary

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Question 11 : Which of the following is not true about diverging lens

 they form virtual, erect and smaller images of real object

 the principal focus is positive

 they poduce virtual images only

 the principal focus is ngative

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Question 12 : In an experiment to determine the focal length of a convex lens, 1/u $\left(c{m}^{-1}\right)$ was plotted on horizontal and 1/v $\left(c{m}^{-1}\right)$ on the vertical axis, where u and v have their usual meaning. What is the physical significance of the reciprocal of the slope of the graph?

 focal length

 object distance

 image distance

 linear magnification

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Question 13 : Which of the following is NOT true about a rheostat?

 It is a resistor with moving contact

 It is a constant current instrument

 It is used for varying the resistance in a circuit

 It is used for varying the current in a circuit

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Question 14 : Calculate the distance and magnification of an object placed 20cm from a converging lens

 60cm and 0.3 times the size of object

 60cm and 3 times the size of object

 20cm and 0.3 times the size of object

 80cm and 3 times the size of object

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Question 15 : Which of the following precautions is NOT applicable to experiment involving planoconvex lens?

 the surface of the lens should be cleaned properly

 the tip of the optical pin should be at the same level with the principal axis of the lens

 parallax error should be avoided

 planoconvex lens should have small focal length

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Question 16 : The potentiometer wire plays equivalent role of which of these devices in a circuit?

 rheostat

 galvanometer

 thermostat

 ammeter

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Question 17 : Which of these is not a useful precaution in an electrical experiment?

 key should be removed between readings to avoid battery run-down

 readings should be recorded as soon as they are obtained

 the connections in the circuit should be tight

 jockeys should be dragged on resistance wires

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Question 18 : The advantage of potentiometer over voltmeter in measurements of emf is that

 faults may arise due to breaks or wrong connections in the circuit

 the potentiometer wire is assumed to be uniform

 the temperatue of the wire must remain constant

 it does not draw current from the circuit under test

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Question 19 : In the circuit diagram shown, the device marked X is a —————–

 galvanometer

 rheostat

 voltmeter

 jockey

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Question 20 : For a metallic conductor, Ohm’s law holds provided

 potential difference remains constant

 temperature remains constant

 current remains constant

 potential difference varies

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