Author Question: What is the uncorrected near point of a person who has a near point that is 25 cm from his eyes when ... (Read 117 times)

jon_i · **on:** Jul 29, 2018

What is the uncorrected near point of a person who has a near point that is 25 cm from his eyes when he is wearing 3.33-diopter contact lenses?

A) 1.9 m B) 0.75 m C) 0.60 m D) 1.5 m E) 0.50 m

Question 2

An 800-kHz sinusoidal radio signal is detected at a point 2.1 km distant from a transmitter tower. The electric field amplitude of the signal at that point is 0.80 V/m.

Assume that the signal power is radiated uniformly in all directions and that radio waves incident upon the ground are completely absorbed. What is the intensity of the radio signal at that point? (0 = 8.85 10-12 C2/N m2, 0 = 4 10-7 T m/A, c = 3.0 108 m/s)
A) 8.5 10-4 W/m2
B) 1.2 10-3 W/m2
C) 1.7 10-3 W/m2
D) 6.0 10-4 W/m2
E) 4.2 10-4 W/m2