Aman stands still on a moving walkway and a woman walks past him in the
same direction as the escalator. to a stationary observer, the man has a
speed of 0.3 m/s and the woman has a speed of 0.38 m/s. from the frame of
reference of the man on the escalator, how fast is the woman walking?
oa. 0.3 m/s
ob. 0.38 m/s
oc. 0.08 m/s
od. 0.68 m/s

Assume similar data for the motion of the blood in your aorta. estimate how many beats of the heart it will take the blood to get from your heart to your brain. (assume that the distance from your heart to your brain is 30 cm)

Which best represents the law of conservation of mass ?

Two loudspeakers, 5.5 m apart and facing each other, play identical sounds of the same frequency. you stand halfway between them, where there is a maximum of sound intensity. moving from this point toward one of the speakers, you encounter a minimum of sound intensity when you have moved 0.33 m . assume the speed of sound is 340 m/s. part a) what is the frequency of the sound? part b) if the frequency is then increased while you remain 0.21 m from the center, what is the first frequency for which that location will be a maximum of sound intensity? express your answer to two significant figures and include the appropriate units.