Question

A flea jumps by exerting a force of 1.27 10-5 N straight down on the ground. A breeze blowing on the flea parallel to the ground exerts a force of 1.20 10-6 N on the flea. Find the direction and magnitude of the acceleration of the flea if its mass is 6.0 10-7 kg. (Let us assume that Fwind points to the right. We will consider this to be the +x direction and vertical to be the +y direction.)

Answer 1

Since force is a vector quantity, we can find the net force by determining the resultant force. The equation is written below:

F = √(Fx²)+(Fy)²
where 
Fx is the force parallel to the ground
Fy is the downward force
F = √(1.2×10⁻⁶ N)²+(1.27×10⁻⁵ N)²
F = 1.2788×10⁻⁵ N

Then, we apply Newton's second law of motion.
F = ma
a = F/m = 1.2788×10⁻⁵ N/(6×10⁻⁷ kg)
a = 21.31 m/s²

The magnitude of the acceleration is 21.31 m/s². The direction is shown in the picture, which is headed towards southeast.