Firemen are shooting a stream of water at a burning buildingusing a high-pressure hose that shoots out the water with a speedof 25.0 m/s. as it leaves the end of the hose. Once it leaves thehose, the water moves in projectile motion. The firemen adjust theangle of elevation α of the hose until the water takes3.00 s to reach the building 45.0 m away. You can ignore airresistance; assume that the end of the hose is at grounglevel.
a) Find the angle of elevation αb) Find the speed and acceleration of the water at the highestpoint in its trajectoryc) How high above the ground does the water strike thebuilding, and how fast is it moving just before it hits thebuilding?

You are sitting on the beach and wondering about the properties of mechanical waves. describe them in terms of ocean waves.

The membrane surrounding a living cell consists of an inner and an outer wall that are separated by a small space. assume that the membrane acts like a parallel plate capacitor in which the effective charge density on the inner and outer walls has a magnitude of 7.0 × 10-6 c/m2. (a) what is the magnitude of the electric field within the cell membrane? (b) find the magnitude of the electric force that would be exerted on a potassium ion (k+; charge = +e) placed inside the membrane.

Fft review: linspace, fs, fftshift, nfft 1. generate one second of a cosine of w,-10hz sampled at f, = 100hz and assign it to x. define a tt as your time axis 2. take 64 points fft. 3. as you remember, the dft (which the fft implements) computes n samples of s2t where k-0,1,2, n -1. plot the magnitude of this 64-points fft at range 0 to 63, what do you think of this graph? 4â·to get the x-axis into a hz-frequency form, plot this 64-points fft between-50 to 50 (the 100hz sampling rate) and have n-points between them. 5. according to your figure, what frequency is this cosine wave at? 6. remember that the fft is evaluating from 0 to 2ď€. we are used to viewing graphs from-ď€ to ď€. therefore, you need to shift your graph. 7. now according to your shifted graph. what frequency is this at? 8. note that the spikes have long drop-offs? try a 1024-point dft. note that the peak is closer to 10 and the drop-off is quicker. although, now sidelobes are an issue