ITEM 7: Photovoltaic (PV) panels receive a broad spectrum of light during the daytime. The spectrum includes short wavelength ultraviolet radiation to longer wavelength infrared radiation. Which of the following is a true statement concerning PV panels and solar radiation? a. PV panels respond most favorably to the visible part of the spectrum. b. Shorter wavelength photons will not trigger the photoelectric effect. c. Longer wavelength photons will be absorbed, but cause heating of the panel. d. All of the above are true statements.

1.what is where an object is located 2. what is how fast an objects speed is changing 3. what is how fast an object is moving

Asynthetic fiber used in manufacturing carpet has tensile strength that is normally distributed with mean 75.5 psi and standard deviation 3.5 psi. how is the standard deviation of the sample mean changed when the sample size is increased from n equals 8 to n equals 47

Amass m = 74 kg slides on a frictionless track that has a drop, followed by a loop-the-loop with radius r = 18.4 m and finally a flat straight section at the same height as the center of the loop (18.4 m off the ground). since the mass would not make it around the loop if released from the height of the top of the loop (do you know why? ) it must be released above the top of the loop-the-loop height. (assume the mass never leaves the smooth track at any point on its path.) 1. what is the minimum speed the block must have at the top of the loop to make it around the loop-the-loop without leaving the track? 2. what height above the ground must the mass begin to make it around the loop-the-loop? 3. if the mass has just enough speed to make it around the loop without leaving the track, what will its speed be at the bottom of the loop? 4. if the mass has just enough speed to make it around the loop without leaving the track, what is its speed at the final flat level (18.4 m off the ground)? 5. now a spring with spring constant k = 15600 n/m is used on the final flat surface to stop the mass. how far does the spring compress?