Aman is crossing a river of width 100 m on a motorboat. the velocity of the motor boat is 4 m/s eastward and the velocity of the water current is 3 m/s northward. what is the resultant velocity of the boat and how much time will it take for the man to reach the other shore of the river? a) the resultant velocity of the motor boat is 5 m/s and it takes 20s to cross the river. b) the resultant velocity of the motor boat is 25 m/s and it takes 5s to cross the river. c) the resultant velocity of the motor boat is 6 m/s and it takes 20s to cross the river. d) the resultant velocity of the motor boat is 4 m/s and it takes 33s to cross the river.

An object is moving east, and it’s velocity changes from 65m/s to 25m/s in 10 seconds. which describes the acceleration?

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

James is trying to prove newton's 2nd law of motion. he tries to move four different objects with different masses, shapes, and sizes from point a to point b. the objects are a toy car, a car, a refrigerator, and a kitchen table. after some experimentation, he finds that force is dependent on the mass of the object, rather than it's size or shape. the object that takes the most force to move is the