<h3>One reason we should know what the directions of the forces acting on an object is so we can know if we have to add or subtract. same = add together, opposite = subtract from each other. Also if we don't pay attention to the direction the Net force will be wont be accurate. There will be factors that will upset the calculation.So we must know the direction of the two forces because we have to know if we are adding or subtracting and if the answer is accurate. </h3>
<em>I hope this helps!.</em>
Answer:
D. The sum total of all matter and energy
Explanation:
The universe is defined as a closed system that contains all forms of energy and matter. Therefore, includes the so-called dark matter and dark energy, which make up most of the universe, since ordinary matter would only represent just over 5% of the total.
Answer:
Take notes
Explanation:
Cuz it helps you stay on task
Answer:
All of the statements are correct
Explanation:
Hello!
All of the statements are rigth. You can know this by examining the Lorentz Force:

a )
The dependence on the charge sign can be inferrend by the term q which is the particle's charge. If it changes sign, the force also does.
b)
Although we usually deal with constant magntic Fields, they could also be position dependent, for example the magnetic field of a wire. The fild of teh force will also inherit this position dependence, that is:

c)
d)
Again, from the equation of the force or Lorentz force, we can see that this statement is true.
d)
The validity of this statement is given by the cross product between the velocity (which points twoards the direction of motion of the particle) and the magnetic field