Answer:
total mass (m) of that substance divided by the total volume (V) occupied by that substances
Answer: 24.7 km/h
Explanation:
1) Average speed definition and formula
The average speed is the total distance run divided by the time elapsed:
S = distance / time
2) Distance 1 = 67 km
3) Distance 2 = 81 km
4) Total distance traveled = 67 km + 81 km = 148 km
5) time 1 = 1 hour
6) time 2 = 5 hours
7) total time = time 1 + time 2 = 1 h + 5 h = 6 h
8) Average speed:
S = 148 km / 6 h = 24.7 km/h
Answer:
1. B. Increase
2. A. Decrease
Explanation:
To understand this issue, we need to put some values and using the ohm's law we can corroborate the two situations.
Ohm's law:
![V = I*R\\where:\\I = current[A] ampers\\R = resistance [ohms]\\V = voltage [volts]\\](https://tex.z-dn.net/?f=V%20%3D%20I%2AR%5C%5Cwhere%3A%5C%5CI%20%3D%20current%5BA%5D%20ampers%5C%5CR%20%3D%20resistance%20%5Bohms%5D%5C%5CV%20%3D%20voltage%20%5Bvolts%5D%5C%5C)
Now for the voltage we will use V = 110 [V], for resistance R = 10 [ohms]
Replacing the values we have:
![I = \frac{V}{R} \\\\I = \frac{110}{10}\\I= 11 [amp]](https://tex.z-dn.net/?f=I%20%3D%20%5Cfrac%7BV%7D%7BR%7D%20%5C%5C%5C%5CI%20%3D%20%5Cfrac%7B110%7D%7B10%7D%5C%5CI%3D%2011%20%5Bamp%5D)
Now let's double the voltage 220 [V]:
![I = \frac{220}{10} \\I = 22 [amp]\\](https://tex.z-dn.net/?f=I%20%3D%20%5Cfrac%7B220%7D%7B10%7D%20%5C%5CI%20%3D%2022%20%5Bamp%5D%5C%5C)
Therefore the current will be increased.
Let's do the same for the resistance if originally we have R = 10 [ohms]
![I = \frac{V}{R}\\I = \frac{110}{10} \\I = 11 [amp]\\](https://tex.z-dn.net/?f=I%20%3D%20%5Cfrac%7BV%7D%7BR%7D%5C%5CI%20%3D%20%5Cfrac%7B110%7D%7B10%7D%20%5C%5CI%20%3D%2011%20%5Bamp%5D%5C%5C)
Now let's double the resistance 20 [ohms]:
![I=\frac{110}{20}\\I = 5.5 [amp]](https://tex.z-dn.net/?f=I%3D%5Cfrac%7B110%7D%7B20%7D%5C%5CI%20%3D%205.5%20%5Bamp%5D)
Therefore the current will be decreased.
<span>Letter
C has the correct illustration. Two objects with the same charge (in this case,
both are positively charged) will repel each other. </span>
Letter
A is incorrect because a positive charged object will attract a negatively
charged object.
Letter
B is incorrect because both of them are negatively charged, which means they
should be repelling each other.
