Farhana is late for class and she is ready to do anything to get to school on time. She knows a mattress truck passes her balcony exactly at 8:42 a.m, travelling at a constant 40km/h. If her balcony is 8.21m from the ground and the truck has a height of 3.47. How far must the truck be from the balcony for Farhana to land on it.
Now i know, we have to find Δ d, and v1= 40km/h or 11.1111111111 m/s.
Δd= v1Δt+ 1/2 aΔt^2
The Attempt at a Solution
Δd= 8.21m- 3.47m
= 4.74/ 11.111111111
= 0.4266 s
Now it's asking how far the truck has to be, so it is asking for distance, and distance is speed over time. But i don't know how to find time. i tried but am i doing it right?