<p>In a hot day the pilot off-loads the plane because:
A) Upthrust offered by hot air is less as compared to that of cold air.
B) Due to decrease in pressure of the atmosphere.
C) Expansion is more in hot days.
D. All of the above.</p>
<p>I don’t even take physics but I’d have to go with C) for this one.</p>
<p>A) Upthrust offered by hot air should be more than upthrust of cold air, just because of simple physics (also hot air rises…).
B) This isn’t even correct. There’s a gas formula P1/T1 = P2/T2. (P = pressure, T = Temperature), so this doesn’t even make sense factually.
C) Only choice that makes logical sense.
D) It can’t be all of the above because none of the other ones make sense.</p>
<p>I might be completely off though, considering I’ve never taken physics.</p>
<p>Im not sure your logic for a is right
upthrust is F=density x volume x 9.81 hence since hot gases have lower density they offer less upthrust. but im not sure if my logic is right </p>
<p>Does anyone know the answer?</p>
<p>@muneebrocks It’s A. Third paragraph here <a href=“factors affecting the performance of aircraft”>http://www.pilotfriend.com/training/flight_training/aft_perf.htm</a></p>
<p>Thank you so much</p>