Question

An eagle has a forward force due to its wings of 6 N. The drag force of the air is 4 N backwards, and its lift force and force of gravity are 20 N upwards and downwards, respectively. What is the net force on the bird?
A. 30 N
B. 1 N forwards
C. 2 N forwards
D. 2 N backwards

Answer 1

You need to solve for the force in all the directions. We're lucky none of these are at angles (:

Answer 2

Solve for forces in the x direction
6 N of forward force, 4 N of backward force (drag, a form of friction that opposes motion, you could say)
\[F_{x} = 6 - 4 = 2N\]
Solve for forces in the y direction. 20N of lift and gravity respectively. Lift is an upward force and gravity is a downward force, so they negate each other.
\[F_{y} = 20 - 20 = 0N\]

What do you think the net force is?

Answer 3

2N I think.

Answer 4

In what direction?

Answer 5

Forwards I was thinking

Answer 6

Correct

Answer 7

Thank you :)