A car drives at a constant speed of 3 m/s around a circle with radius 20 m. What is the centripetal acceleration of the car?
A. 0.45 m/s2
B. 0.15 m/s2
C. 6.7 m/s2
D. 9.2 m/s2

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.

Which inventor was often called the lady edison

50 points to who answers this question in a clear and simple explanation : to what hight will a mass of weight of 500 n be raised in 20 seconds by a motor using 4kw of power?