Author Question: John is nearsighted and cannot see things beyond 90 cm from his eyes. What is the refractive power ... (Read 65 times)

Tirant22 · **on:** Jul 29, 2018

John is nearsighted and cannot see things beyond 90 cm from his eyes. What is the refractive power of the contact lenses that will enable him to see distant objects clearly?

A) +1.1 diopters
B) -1.1 diopters
C) -1.7 diopters
D) -2.2 diopters
E) +2.2 diopters

Question 2

What is the net power that a dog with surface area of 0.075 m2 radiates if his emissivity is 0.75, his skin temperature is 315 K, and he is in a room with a temperature of 290 K? The Stefan-Boltzmann constant is 5.67 x 10-8 W/(m2K4).

A) 9.0 W
B) 6.0 W
C) 8.0 W
D) 15 W
E) 18 W