Answer: because they have equal numbers of protons
Explanation: Atoms are electrically neutral because they have equal numbers of protons (positively charged) and electrons (negatively charged). If an atom gains or loses one or more electrons, it becomes an ion
The average speed of a moving object is the rate of change of a certain distance with respect with time. It is equal to the total distance that was traveled by the object over the total time it takes to travel that distance. For this problem we need to assume that the total distance that was traveled would be equal to 120 miles. So, for the first half of the distance or 60 miles at a speed of 30 miles per hour, the time taken would be two hours. For the remaining 60 miles at a speed of 60 miles per hour, 1 hour is total time traveled. So, we calculate the average speed as follows:
Average speed = total distance / total time
Average speed = 120 miles / 2 hr + 1 hr
Average speed = 40 mi / hr
Density of copper: 8,9
Density of steel: 7,7
Density of aluminum: 2,7
And
Resistivity of copper: 1,7
Resistivity of steel: 16,9
Resistivity of aluminum: <span>2,7</span>
Hope I Helped You!!! :-)
Have A Good Day!!!
