There are four main forces operating on an aeroplane, the relationship between them in terms of ‘balance’ determining whether the plane climbs, cruises or descends. These are shown in the diagram:
Draw the aeroplane climbing away from the runway at take off, cruising at a constant height mid-flight and then descending prior to landing. Use arrows to represented the magnitude of the various forces at each of the three stages of flight.
NB: Gravitational force remains constant throughout, the pilot can only adjust (either directly or indirectly) lift, thrust and drag.
The conventions to adopt when representing forces using arrows are:
Direction of arrows represent forces having direction
Straightness of arrows represent forces acting in straight lines
Length of arrows represents the magnitude of forces
Location of arrows’ tails represents objects as point masses
Arrows of unequal lengths represent unbalanced forces
Arrows drawn in different directions represent both forces influence resultant movementThe Physics of Falling