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
<span>Answer: "a cold front" .
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Answer:
A. If the sum of the external forces on an object is zero, then the object must be in equilibrium
Explanation:
Equilibrium, in physics, the condition of a system when neither its state of motion nor its internal energy state tends to change with time.
For a single particle, equilibrium arises if the vector sum of all forces acting upon the particle is zero.
the object is at equilibrium, then the net force acting upon the object should be 0 Newton. Thus, if all the forces are added together as vectors, then the resultant force (the vector sum) should be 0 Newton.
There are three types of equilibrium: stable, unstable, and neutral
Most reactions are exothemic. If the forward reaction of an equilibrium reaction is exothemic then the reverse reaction must be endothermic.
If a system in equilibrium is heated, it will move in exothermic direction to give out heat energy.
This is the answer "Some active leisure activities, such as yoga and running, require a great deal of physical energy, while other activities, like playing chess, require a substantial amount of mental energy. Passive leisure activities, such as watching TV or going to the movies, require little to no physical or mental energy. Because of the exertion of physical or mental energy, active leisure activities have more health benefits than passive leisure activities." hope it help you?:)
