7. A block of wood is moved 30cm along a rough surface. If the mass of wood is 25kg and the coefficient of friction is 0.8. What is the minimum work done

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.

Give your knowledge of these things in your paper, you will compare and contrast analog and digital signals to determine which is more reliable for encoding and transmitting information. you’ll compare these features: signal shape numerical values for signal measurements amount of data that can be transmitted energy requirements privacy and security (ability of the signal to be encoded in a secret code) clarity of signal in the space provided, write down what you already know about any of these features. if you’re not sure, write down questions you might have about the features.

Air is contained in a variable-load piston-cylinder device equipped with a paddle wheel. initially, air is at 400 kpa and 17°c. the paddle wheel is now turned by an external electric motor until 75 kj/kg of work has been transferred to air. during this process, heat is transferred to maintain a constant air temperature while allowing the gas volume to triple. calculate the required amount of heat transfer in kj/kg.