Answer:
2.4564 m/s
Explanation:
Number of waves in 1 second
This is the frequency 0.267 Hz
The distance mentioned in the question is the
= Wavelength = 9.2 m
The speed of wave is
The speed of the wave is 2.4564 m/s
The car traverses a distance 
after time 
according to
where 
is its acceleration, 10 m/s^2. The time it takes for the car to travel 25 m is
5 is pretty close to 4, so we can approximate the square root of 5 by 2. Then the car's velocity 
after 2 s of travel is given by
which makes C the most likely answer.
Answer:
W = 1.545E6 J total work
P = W / t = 1.545E6 J / 3 sec = 5.15E5 J/sec = 515,000 J/sec (Watts)
Using definition of power
The short answer is that the displacement is equal tothe area under the curve in the velocity-time graph. The region under the curve in the first 4.0 s is a triangle with height 10.0 m/s and length 4.0 s, so its area - and hence the displacement - is
1/2 • (10.0 m/s) • (4.0 s) = 20.00 m
Another way to derive this: since velocity is linear over the first 4.0 s, that means acceleration is constant. Recall that average velocity is defined as
<em>v</em> (ave) = ∆<em>x</em> / ∆<em>t</em>
and under constant acceleration,
<em>v</em> (ave) = (<em>v</em> (final) + <em>v</em> (initial)) / 2
According to the plot, with ∆<em>t</em> = 4.0 s, we have <em>v</em> (initial) = 0 and <em>v</em> (final) = 10.0 m/s, so
∆<em>x</em> / (4.0 s) = (10.0 m/s) / 2
∆<em>x</em> = ((4.0 s) • (10.0 m/s)) / 2
∆<em>x</em> = 20.00 m
