An electric device delivers a current of [tex]$15.0 A$[/tex] for 30 seconds. How many electrons flow through it?
Answer (2)
To solve this problem, we need to understand how currency exchange rates work. An exchange rate tells us how much one currency is worth in terms of another currency.
In this case, 5 yuan is equivalent to 1 US dollar. This means to convert yuan into US dollars, we divide the number of yuan by the exchange rate.
Here's the step-by-step process:
Identify the cost in yuan: The painting costs 50 yuan.
Use the exchange rate: The exchange rate is 5 yuan per US dollar.
Convert yuan to dollars: To find out how many US dollars the painting costs, divide the cost in yuan by the exchange rate:
Cost in US dollars = Exchange rate Cost in yuan
Calculate: Substitute the given values:
Cost in US dollars = 5 50 = 10
Therefore, the painting will cost 10 US dollars .
The correct answer is option $10.
Around 2.81 x 10^21 electrons flow through the device delivering a current of 15.0 A for 30 seconds. This is calculated using the relationship between current, charge, and the charge of an electron. Total charge is found by multiplying current by time, which is then divided by the charge of a single electron to find the number of electrons.
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