Human skin (choose all that apply)
1. emits radiation well.
2. absorbs radiation well.
3. does not emit radiation well.
4. does not absorb radiation well.
5. has an emissivity of 0.
1 and 2 only :)
I agree. Human skin does most of its radiating in the 3 to 10 micrometer region of the infrared. Its average emissivity there is 0.97 of that of a black body, regardless of ethnicity. The average absorptivity for (visible) sunlight is lower, but still a rather high number.
a batter hits a baseball so that it leaves the bat with an initial velocity of 37.0 meter per seconds at an initial angle of 53.1 degrees, at a location where gravity is 9.8 meter per seconds squared. find the position of the ball and the magnitude and direction of its velocity, when time is equal to seconds. find the time when the ball reaches the highest point of its flight and find its height at this point. find the horizontal range r- that is the horizontal distance from the starting point, the point at which the ball hits the ground.for each treat the baseball as a projectile.
To determine which statements about human skin are correct, let's break down the options one by one:
1. Emits radiation well: Human skin does emit radiation, but the degree to which it emits depends on various factors. However, it does emit thermal radiation, especially at longer wavelengths within the infrared spectrum. So, this statement is generally correct.
2. Absorbs radiation well: Human skin does absorb certain wavelengths of radiation from the environment. For example, it absorbs ultraviolet (UV) radiation from the sun, which can cause damage to the skin. So, this statement is generally correct.
3. Does not emit radiation well: This statement contradicts the first option (1), which indicated that human skin does emit radiation. Therefore, this statement is not correct.
4. Does not absorb radiation well: This statement contradicts the second option (2), which stated that human skin does absorb certain wavelengths of radiation. So, this statement is not correct.
5. Has an emissivity of 0: Emissivity is a measure of how well a material emits radiation compared to a perfect blackbody radiator (which has an emissivity of 1). Human skin has an emissivity that is not zero, but it is relatively low, typically around 0.98. So, this statement is not correct either.
Based on these explanations, the correct statements about human skin would be options 1 and 2: Human skin emits radiation well and absorbs radiation well.