What's now called "Conventional current" is thought of as the flow of positive charge, from the battery's positive terminal to its negative one.
But it turns out that positive charges don't flow. The physical flow of charge is the flow of electrons. They come out of the battery's negative terminal, and carry negative charge around the circuit to the battery's positive one.
Answer:
a. It always points perpendicular to the contact surface.
Explanation:
"Normal" means perpendicular. Normal forces are always perpendicular to the contact surface.
The free-body diagram of an apple falling through the air has weight of the apple pointing downwards and the air-resistance on the apple acting upwards.
When an object falls from up to the ground, the object falls under in the influence of acceleration due to gravity.
The vertical component of the force on the apple as it falls trough the air is given as;
∑Fy = 0
Fₙ - W = 0
Fₙ = W
where;
- <em>Fₙ is the frictional force on the apple acting upwards</em>
- <em>W is the weight of the apple acting downwards</em>
The free-body diagram of the apple is represented as follows;
↑ Fₙ
Ο
↓ W
Thus, the free-body diagram of an apple falling through the air has weight of the apple pointing downwards and the air-resistance on the apple acting upwards.
Learn more here:brainly.com/question/18770265
Question 18: a
question 19: b
question 20: c