An electric device delivers a current of [tex]$15.0 A$[/tex] for 30 seconds. How many electrons flow through it?
Answer (2)
A device with a current of 15.0 A for 30 seconds carries about 2.81 × 1 0 21 electrons. This is found by calculating the total charge and then converting that charge to the number of electrons using the charge of a single electron. Thus, the answer is a pp ro x ima t e l y 2.81 × 1 0 21 electrons.
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List percentages: Russia (1.1%), France (1.5%), UK (0.24%), Italy (1.6%), Serbia (5.7%), US (0.1%).
Identify smallest percentages: US (0.1%) and UK (0.24%).
The two countries with the smallest percentage of population lost are the US and the UK.
Final answer: \boxed{the US and the UK}
Explanation
Analyze the problem The table provides the percentage of population lost for each country. We need to identify the two countries with the smallest percentages.
List the percentages Here are the percentages of population lost for each country:
Russia: 1.1%
France: 1.5%
UK: 0.24%
Italy: 1.6%
Serbia: 5.7%
US: 0.1%
Identify the smallest percentages The two smallest percentages are 0.1% (US) and 0.24% (UK).
Identify the countries Therefore, the two countries that lost the smallest percentage of their populations are the US and the UK.
Examples
Understanding percentages helps us compare different groups. For example, if we want to compare the impact of a disease on two cities with different populations, we can use percentages to get a clearer picture. If City A has 1000 people and 100 are infected, the infection rate is 1000 100 = 10% . If City B has 10,000 people and 500 are infected, the infection rate is 10000 500 = 5% . Even though City B has more infected people, City A has a higher percentage of its population infected.
