A balloonist drops an apple weighing 1.5 N over the side of the balloon's gondola. As it falls and increases speed, the drag force from the air upward on it increases. When the upward force is 0.7 N, what is the direction and magnitude of the net force on the apple?
0.8 N downward
To determine the direction and magnitude of the net force on the apple, we need to consider the forces acting on it.
In this scenario, we have two forces acting on the apple: the weight force (downward) and the drag force (upward).
1. Weight force (downward): The weight force is the force exerted on an object due to gravity. The weight force is equal to the mass of the object multiplied by the acceleration due to gravity (9.8 m/s^2 on Earth). Since we know the weight force is 1.5 N, we can calculate the mass of the apple.
Weight force = mass × acceleration due to gravity
1.5 N = mass × 9.8 m/s^2
Solving for mass:
mass = 1.5 N / 9.8 m/s^2
mass ≈ 0.153 kg
2. Drag force (upward): The drag force is caused by the air resistance acting in the opposite direction to the motion of the apple. We are given that the drag force is 0.7 N.
Now, let's determine the net force acting on the apple.
Net force = Drag force - Weight force
Net force = 0.7 N - 1.5 N
Net force = -0.8 N
The negative sign indicates that the net force is directed downward, opposite to the upward direction of the drag force.
Therefore, the direction of the net force on the apple is downward, and the magnitude of the net force is 0.8 N.