To find the total distance traveled by the car, you first calculate the distance traveled by the car when it travels to north. You use the following formula:
x: distance
t: time
v: speed
In order to calculate the distance you convert the time from hours to seconds:
t = 0.5h * 3600s /1h = 1800s
![\begin{gathered} x=vt \\ x=30m/s\cdot1.800s \\ x=54000m \\ x=54\operatorname{km} \end{gathered}]()
Next, you calculate the distance traveled by the car when it travels to south:
You convert the time from minutes to seconds:
t = 15min*60s/1min = 900s
![\begin{gathered} x=vt \\ x=40m/s\cdot900s \\ x=36000m \\ x=36\operatorname{km} \end{gathered}]()
Finally, you sum both distances
Total distance = 54 km + 36 km = 90km
The total displacement is the final distance of the car respect to the starting point of the motion. This is calculated by subtracting
d = 54km - 36km = 18km
The total distance traveled by the car is 90km
The total displacement of the car is 18km to the north from its starting point of motion.
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