PLEASE HELP ME IF YOU KNOW STUFF ABOUT ENERGY TYSM

Physics make-up packetname_cle14. an observer hears a sound with a frequency of 400 hz. if the speed of sound is 340 m/s,what is the wavelength of the sound? a. 0.85 mb. 1.2 mc. 2.75 m13.6 m15. as sound travels from steel into air, its speed decreases. if the frequency of the wavedoesn't change, what happens to its wavelength? a. it increases(b) it decreasesc. it remains the samed. there is not enough information given

A0.580-kg rock is tied to the end of a string and is swung in a circle with a radius of 0.500 meters. the velocity of the rock is 4.50 m/s. what is the centripetal force acting on the rock? 15.5 n 5.22 n 69.8 n 23.5 n

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