The cornea behaves as a thin lens of focal length approximately 1.8 cm, although this varies a bit. The material of which it is made has an index of refraction of 1.38, and its front surface is convex, with a radius of curvature of 5.0 mm. a. If this focal length is in air, what is the radius of curvature of the back side of the cornea?
b. The closest distance at which a typical person can focus on an object (called the near point) is about 25 cm, although this varies considerably with age. Where would the cornea focus the image of an 8.0-mm-tall object at the near point?
c. What is the height of the image in part (b)? Is this image real or virtual? Is it erect or inverted?

Dalton’s model of an atom is the best described as a) a solar system b) a solid sphere c) a cloud d) a scoop of chocolate chip ice cream

We want to calculate the total metabolic heat generated by a singing canary taking into account heat transfer by radiation, convection and exhaling air. the air temperature is 20 oc, canary’s body internal and surface temperature is 33oc, external body surface convective heat transfer coefficient is 25.2 w/m2 .k, temperature difference between the inhaled and exhaled air is 4.3 oc, the ventilation rate is 0.74 cc of air per second, specific heat of air is 1.0066 kj/kg.k and density of air is 1.16 kg/m3 . assume the canary’s body to be a cylinder with 7 cm diameter and 9 cm length, and heat exchange is from the side as well as the top and bottom of cylinder. calculate 1) the net rate of heat lost by radiation, assuming heat gained by the bird through radiation from the surroundings is 11.5 w; 2) rate of heat transferred by convection to the surrounding air; 3) rate of heat transferred in the exhaling air without considering any internal evaporation; 4) total metabolic power.

Why does karst topography exist in some geographic location? a. few climates have enough oxygen b. most regions have rock layers other than limestone c. in most regions, the soil is too thin d. the water is too acidic enough in most places