Answer:
the name of the SI unit for force is the newton
Because it generates enough momentum to keep the train going with out really having to speed up
Answer:
2.98 m/s^2
Explanation:
I have done this before and it was a question on my physics test
<span>Let's convert the speed to m/s:
speed = (55 mph) (1609.3 m / mile) (1 hour / 3600 seconds)
speed = 24.59 m/s
Let's convert the mass to kilograms:
mass = (2135 lb) (0.45359 kg / lb)
mass = 968.4 kg
We can find the kinetic energy KE:
KE = (1/2) m v^2
KE = (1/2) (968.4 kg) (24.59 m/s)^2
KE = 292780 joules
The kinetic energy of the automobile is 292780 joules.</span>
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
