A person's eye lens is 2.8 cm from the retina, and his near point is at 25 cm. What must be the focal length of his eye lens so that an object at the far point of the eye will focus on the retina?
A) -2.8 cm
B) 2.8 cm
C) -2.4 cm
D) 2.4 cm
E) 2.2 cm
B
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Decreasing the resistance of an ammeter's shunt resistance
A) converts it to a voltmeter. B) allows it to measure a larger current at full scale deflection. C) allows it to measure a smaller current at full scale deflection. D) enables more current to pass directly through the galvanometer.
Define the solid angle.
What will be an ideal response?
A circumferential cast iron fin attached to a compressor housing is 1 inch thick, 3 in long, 3 in diameter, and the convective heat transfer coefficient is 16 Btu/hr?ft^2? ºF. If the base temperature is 160ºF and the surrounding air is 80ºF, determine the fin efficiency and the heat transfer through the fin.
What will be an ideal response?
The period T of the fundamental mode of the air in a pipe open at one end and closed at the other is equal to what multiple or fraction of the time ?t required for a sound wave to travel from one end of the tube to the other?
A. T = ?t/4 B. T = ?t/2 C. T = ?t D. T = 2?t E. T = 4?t