Answer:
A vacuum is an area without any air, like space. So sound cannot travel through space because there is no matter for the vibrations to work on it.
Yup the correct answer is A jus finished the quiz :)
hope i helped^_^
The first scientist was Mendeleev
The first A.C. system in the United States was built by
B. Michael Faraday
5. The jogger's velocity is a constant 3.55 m/s between t = 4 s and t = 8 s.
6. Given a linear plot of velocity, the acceleration is determined by the slope of the line. Take any two points on the part of the plot after t = 8 s - for instance, we see it passes through (8 s, 3.5 m/s) and (10 s, 4 m/s) - and compute the slope:
(4 m/s - 3.5 m/s)/(10 s - 8 s) = (0.5 m/s)/(2 s) = 0.25 m/s^2
7. This amounts to finding the area between the velocity function and the time axis and between t = 4 s and t = 8 s. During this time, the velocity is 3.5 m/s. The time interval lasts 4 s. So the distance covered is
(3.5 m/s)*(4 s) = 14 m
8. After 4 seconds, Jimmy's speed decreases from 30.0 m/s to 27.2 m/s, so his acceleration (assuming it was constant) was
a = (27.2 m/s - 30.0 m/s)/(4 s) = -0.200 m/s^2
It's unclear what is meant by "rate of acceleration", since the acceleration is itself a rate. But maybe they just mean to ask for the acceleration, or possibly the magnitude?
