Answer:
resonance
Explanation:
The particles of substance B will cause the particle of substance A to vibrate at the same frequency
Answer:
13 N
Explanation:
The Net Force of an object should be the difference between the forces applied to the object if the object is not in equilibrium. This object is not in equilibrium so therefore by finding the difference between the forces, you will find your answer. 20 N - 7 N = 13 N.
In 1920, after returning from Army service, he produced a successful model and in 1923 turned it over to the Northeast Electric Company of Rochester for development.