The frequency of sound will decrease when; a) the source approaches a stationary observer
b) the observer approaches a stationary source
c) the source recedes from a stationary observer
d) the observer recedes from a stationary source
e) both a and b
f) both c and d
g) both a and d
h) both b and c
i) none of these

Karen is running forward at a speed of 9 m/s. she tosses her sweaty headband backward at a speed of 20 m/s. the speed of the headband, to the nearest whole number relative to a stationary observer watching karen

Abeverage can is made of 3004-h19 aluminum alloy (elastic modulus 69 gpa, tensile yield strength 285 mpa, density 2.72 g/cm^3). the dimensions on the can are approximated as a thin-walled cylinder with a height of 4.83 inches, diameter of 2.60 inches. empty the can has a mass of 14.2 g. determine: a. the wall thickness of the cylinder b. assuming a pinned-pinned condition what is the critical load? c. assuming a fixed-fixed condition what is the critical load?

Newton's law of cooling states that the rate of change in the temperature t(t) of a body is proportional to the difference between the temperature of the medium m(t) and the temperature of the body. that is, startfraction dt over dt endfraction equals upper k left bracket upper m left parenthesis t right parenthesis minus upper t left parenthesis t right parenthesis right bracket , where k is a constant. let kequals0.04 left parenthesis min right parenthesis superscript negative 1 and the temperature of the medium be constant, m(t) font size decreased by 3 equivalent font size decreased by 3 294 kelvins. if the body is initially at 369 kelvins, use euler's method with hequals0.1 min to approximate the temperature of the body after (a) 30 minutes and (b) 60 minutes.