(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A jet aircraft climbs in a straight line at an attitudeof 90 degrees to the hozizontal. The jet thrust amounts to 90kN, the mass of the aircraftis 8 tonne and the average air resistance mounts to 11kN. Calculate the time taken to reach a height of 3 km if the speed at the start of the climb is 160Km/h.

2. Relevant equations

u= 160km/hr = 44.4 m/s

a= to be calculated

s= 3000m

t=

S=u*t+ 1/2 at^2

F= m times a

3. The attempt at a solution

vertical acceleration force

79 cos 60 - 8000kg

F=ma

a=f / m

0 = (1/2a) t^2 + (u) t + s

0 = 2.435t^2 + 138.56 t - 3000

am confused.

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# Homework Help: Calclulating time taken

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