A heat pump is a device that puts out heat. It involves pumping a lever over and over to get energy so it can work.
Answer:
5.625km/h
Explanation:
We are given that
Distance between home and market, d=2.5 km
Speed, v1=5km/h
Speed, v2=7.5 km/h
We have to find the average speed of the man over the interval of time 0 to 40min.
Time,
Using the formula

1 hour =60 min

Distance traveled by man in 10 min with speed 7.5 km/h=
Therefore,
Total distance covered=2.5+2.5/2=3.75 km
Time=40 min=40/60=2/3 hour
Average speed=
Average speed=
The distance for any rectilinear motion at constant acceleration is:
d = v₀t + 0.5at²
where
v₀ is the initial velocity
So, if v₀ = 6v, and it stopped to 0 m/s, then the acceleration is equal to:
a = (0 - 6v)/t = -6v/t
Thus,
d = (6v)(t) + (0.5)(-6v/t)(t²)
d = 6vt - 3t
<span>d = 3t(2v - 1)</span>