Respuesta :
Answer:
24 cm
Explanation:
You know the equation for speed: v = Δd/Δt.
This is easy to use to find the distance travelled for the second half of the graph (4-8s) where the speed is constant:
4 = Δd / 4
Δd = 16 cm
For the first part (0-4s), the speed is changing. Since it is changing at a constant rate (i.e. the acceleration is constant), you can find the average speed (lowest speed + highest speed / 2) and use that in the equation above instead. In this case, the average speed is (0 + 4) / 2 = 2 cm/s. Plugging that into the equation above:
2 = Δd / 4
Δd = 8 cm
The total distance traveled is 16cm + 8cm = 24cm.
Answer: the distance traveled in the 8 seconds is equal to 22cm
Explanation: Here we have a graph of speed vs time.
between the seconds 0 and 4, the speed grows linearly with the time as:
v(t) = t*1cm/s^2
and after the second 4s, the speed is constant:
v(t) = 4cm/s
so we can integrate both parts by separated:
1)
the integral of t*1cm/s^2 over the time is equal to:
(t^2)/2 *1cm/s^2 + c
where c is a constant of integration.
If we calculate this between t = 4s and t = 0s, we got:
d1 = (4^2)/2 cm/s^2 + c - (0^2)/2 cm/s^2 - c = 8cm
so in the first 4 seconds, the object traveled 8 cm-
2)
now the integration is easier, v = 4cm/s, then in 4 seconds, the object moves 4cm four times; then we got:
d2 = 4cm/s*4s = 16cm
then the total distance that the object moves in the 8 seconds is:
d1 + d2 = 8cm + 16cm = 22cm