Based on the position vs. time graph, which velocity vs. time graph would correspond to the data? A graph with horizontal axis time (seconds) and vertical axis position (meters). A line runs straight upward from 0 seconds 0 minutes. A graph labeled velocity versus time with horizontal axis time (seconds) and vertical axis velocity (meters per second). A line runs in straight segments from 0 seconds 0 meters per second to 1 second 15 meters per second to 2 seconds 20 meters per second to 4 seconds 20 meters per second to 5 seconds 0 meters per second. A graph labeled velocity versus time with horizontal axis time (seconds) and vertical axis velocity (meters per second). A straight line begins at 0 seconds 0 meters per second and runs to 5 seconds 5 meters per second. A graph horizontal axis time (seconds) and vertical axis velocity (meters per second). A straight line begins at 0 seconds 2 meters per second and runs to 5 seconds 2 meters per second. A graph labeled velocity versus time with horizontal axis time (seconds) and vertical axis velocity (meters per second). A straight line begins at 0 seconds 10 meters per second and runs to 5 seconds 2 meters per second.

To run the physics cart, the fan speed of the cart is manipulated. this is the (blank) variable. the cart accelerates due to the speed of the fan. acceleration is therefore the (blank) variable. a “constant” is a parameter that stays the same regardless of the variables. one parameter of the cart that is held constant is the (blank) .

An internally reversible refrigerator has a modified coefficient of performance accounting for realistic heat transfer processes of where qin is the refrigerator cooling rate, qout is the heat rejection rate, and is the power input. show that copm can be expressed in terms of the reservoir temperatures tc and th, the cold and hot thermal resistances rt,c and rt,h, and qin, as where rtot rt,c rt,h. also, show that the power input may be expressed as 1.39 a household refrigerator operates with cold- and hot-temperature reservoirs of tc 5 c and th 25 c, respectively. when new, the cold and hot side resistances are rc,n 0.05 k/w and rh,n 0.04 k/w, respectively. over time, dust accumulates on the refrigerator’s condenser coil, which is located behind the refrigerator, increasing the hot side resistance to rh,d 0.1 k/w. it is desired to have a refrigerator cooling rate of qin 750 w. using the results of problem 1.38, determine the modified coefficient of performance and the required power input w under (a) clean and (b) dusty coil conditions. internally reversible refrigerator qout qin w high-temperature reservoir low-temperature reservoir th th,i tc,i tc high-temperature side resistance low-temperature side resistance w qin th tc qinrtot tc qinrtot copm tc qinrtot th tc

Unpolarized light of intensity i_0=750w/m^2 is incident upon two polarizers. after passing through both polarizers the intensity is i_2=280w/m^2. (a) what is the intensity of the light after it passes through the first polarizer in w/m^2? (b) write an equation for the angle between the polarizers in terms of the initial (i_0) and final (i_2) intensities. (c) find the angle between the polarizers in degrees.