The correct answer is:
<span>Become positively or negatively charged
In fact, an insulator is a material where charges cannot move freely. Therefore, it can be positively or negatively charge (for example, if it is rubbed against another object, the insulator can remain with an excess of charge), but it cannot transfer charge to other objects.</span>
Answer:
.
Explanation:
The frequency
of a wave is equal to the number of wave cycles that go through a point on its path in unit time (where "unit time" is typically equal to one second.)
The wave in this question travels at a speed of
. In other words, the wave would have traveled
in each second. Consider a point on the path of this wave. If a peak was initially at that point, in one second that peak would be
How many wave cycles can fit into that
? The wavelength of this wave
gives the length of one wave cycle. Therefore:
.
That is: there are
wave cycles in
of this wave.
On the other hand, Because that
of this wave goes through that point in each second, that
wave cycles will go through that point in the same amount of time. Hence, the frequency of this wave would be
Because one wave cycle per second is equivalent to one Hertz, the frequency of this wave can be written as:
.
The calculations above can be expressed with the formula:
,
where
represents the speed of this wave, and
represents the wavelength of this wave.
B. Reflection is when waves bounce off a surface Ik this because I did it in 7th grade was my favorite unit to learn in school
Answer:
The average acceleration is 
Explanation:
<u>Uniform Acceleration
</u>
When an object varies its velocity at the same rate, the acceleration is constant.
The relation between the initial and final speeds is:

Where:
vf = Final speed
vo = Initial speed
a = Constant acceleration
t = Elapsed time
The acceleration can be calculated by solving for a:

The Indy 500 race car increases its speed from vo=4 m/s to vf=36 m/s in t=4 s. Thus, the average acceleration is:

The average acceleration is 
5.8x10^3
3.02x10^8
4.5x10^5
8.6x10^10