The 1kg rock is tied to a string and swung in a circular path as shown. The 1 meter string is tied to a post, and during the motion, the string has a 30 angle with the post. The rock makes 100 rounds in 1 minute. The centripetal force on the rock is

Sally turns on her cellular telephone to speak to her friend who is located thousands of miles away. which of the following best describes how such a telephone is able to transmit and receive information? a. the cellular telephone transmits, receives, and encodes information using only sound waves. b. the cellular telephone transmits, receives, and encodes information using only electromagnetic waves. c. the cellular telephone transmits information by electromagnetic waves to a receiver which then encodes them and produces sound. d. the cellular telephone transmits information by sound waves to a receiver which then encodes them and produces electromagnetic waves.