Answer:
E) 800 km/h
Explanation:
The computation of the average vector velocity module of the plane, at that time is shown below:
The displacement vector is
d^2 = d1^2 + d2^2
where,
d1 = northeast displacement
d2 = southeast displacement
Now
d^2 = (120)^2 + (160)^2
= 14400 + 2560
= 40000
= √40000
d = 200 km
Now the average velocity is
V = ΔS ÷ Δt
= 200 ÷ 1 ÷ 4
= 200 × 4
= 800 km/h
Considering conservation of mechanical energy we have:
K+U (start)= K+U (end)
Where:
K=kinetic energy=
![\frac{1}{2}m v^{2}](https://tex.z-dn.net/?f=%20%5Cfrac%7B1%7D%7B2%7Dm%20v%5E%7B2%7D%20%20)
U=potential energy=
![mgh](https://tex.z-dn.net/?f=mgh)
So:
0.05*0.95*9.81+0 (start) = 0+K (end)
K (end)=0.5 Joules
19.6 N........weight is equal to mass multiplied by gravitational force which is 9.8 m/s2......2 x 9.8 gives 19.6 N
Turbine generators to produce electricity.