Question

A jet with mass m = 8 × 104 kg jet accelerates down the runway for takeoff at 1.5 m/s2. What is the net vertical force on the airplane as it accelerates for takeoff?

Answer 1

During the movement down the runway, the jet is only moving horizontally with some acceleration.

It is a very fundamental concept that perpendicular forces do not affect one another.

Therefore, if the jet is not moving up or down while on the runway, the net vertical force MUST be zero.

And indeed it is. Gravity will exert a force (mg) on the jet, while the runway exerts an equal and opposite normal force upwards.

Answer 2

Thanks we thought about it and realized it.