Question

1. A plane designed for vertical takeoff has a mass of 7.5 ✕ 10³ kg. Find the net work done by all forces on the plane as it accelerates upward at 11.9 m/s² through a distance of 30.4 m after starting from rest.
Answer in Joules

2. When catching a baseball, a catcher's glove moves by 9 cm along the line of motion of the ball. If the baseball exerts a force of 483 N on the glove, how much work is done by the ball?
Answer in Joules

Answer 1

Here the force applied by the engine of the plane supplies necessary force to balance the weight of the plane as as well as giving necessary thrust for imparting accelaration f 11.9 m/s2..

so net upward force by the engine F= wight of the plane+upwarf thrust

=7.5*103*9.8 + upward thrust ( * denote for multiplication)

upward thrust=mass* acceleration=7.5*103*11.9 Newton

so F=7.5*103*(11.9+9.8) Newton =16763.25

so work done=F*distanct=16763.25*30.4=509602.8 jule

work done by the ball =force * distance mved =483*(9/100) ,, 9 cm=9/100 m

=43.47 jule