1. "<span>Physical models are usually in the form of a graph" is the statement among the statements given about physical models that is not true. The correct option among all the options that are given in the question is the third option or option "c".
2. "Predicting weather patterns" is the one among the following scenarios that </span>represents the best use of a scientific model. <span>The correct option among all the options that are given in the question is the first option or option "a".</span>
<span>
The taut guitar string haspotencial energy which we can see in action.</span> <span>· so option a is correct.</span>
Answer:0.69
Explanation:
Coefficient of kinetic friction=f/R=61.8/90=0.69
Answer:
the field at the center of solenoid 2 is 12 times the field at the center of solenoid 1.
Explanation:
Recall that the field inside a solenoid of length L, N turns, and a circulating current I, is given by the formula:
Then, if we assign the subindex "1" to the quantities that define the magnetic field (
) inside solenoid 1, we have:

notice that there is no dependence on the diameter of the solenoid for this formula.
Now, if we write a similar formula for solenoid 2, given that it has :
1) half the length of solenoid 1 . Then 
2) twice as many turns as solenoid 1. Then 
3) three times the current of solenoid 1. Then 
we obtain:

Answer:
30N in the direction the 45N acts.
Explanation:
Fnet = F1 + F2 (the vector sum of the forces)
Assigning a positive direction to the 45N force and a negative direction to the 15N force gives:
Fnet = 45 - 15
Fnet = 30N
Since the answer is positive, it is in the direction the 45N force acts.