Remember, that while sped is constant, acceleration is not. Acceleration is when velicity changes. So the graph which shows the slop <span>of a velocity vs time describes acceleration.
</span>If we have the straight line on the graph it means that the slope is always the same whereas the <span>non-linear graphs has a variable slope that changes depending on your point in the graph.
</span>To conclude - if your graph is not a straight line it has variable acc at many points.<span>
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Answer:
The velocity of the truck after the collision is 20.93 m/s
Explanation:
It is given that,
Mass of car, m₁ = 1200 kg
Initial velocity of the car, 
Mass of truck, m₂ = 9000 kg
Initial velocity of the truck, 
After the collision, velocity of the car, 
Let
is the velocity of the truck immediately after the collision. The momentum of the system remains conversed.




So, the velocity of the truck after the collision is 20.93 m/s. Hence, this is the required solution.
Given:
The speed of sound is 340 m/s
Time for the echo is 5.2 s.
Let h = the depth of the canyon.
Because the sound of your voice travels to the bottom of the canyon and back to your ear, the total distance traveled is 2h.
By definition,
distance = velocity * time.
Therefore
2h = (340 m/s)*(5.2 s) = 1768 m
h = 884 m
Answer: The depth is 884 m.