How many electrons make up −1.5 × 10 −5 C?

Alright, guys, let's work this one out together. So how many electrons? So we're looking for a number of electrons. Make up this number right here, and it says units of cool. Um, so I know that this is a charge, so why don't we go ahead and start with using the charge equation? So we've got Q equals we've got number of protons minus number of electrons, and that's equal. Or so we have to multiply by the elementary charge. That's equal to the total charge. So in these kinds of problems, you're gonna usually gonna be given some information about electrons or protons, but not the other one. So notice how we have no information about protons. So what we do In that case, we just assume that's equal to zero. So assume the number of protons zero were interested in how much how maney electrons here make up this amount of charge. So we're only gonna be focusing on the electrons. Hopefully, that makes sense. Let me know if you if you guys have any questions on that part. So this is the total charge right here. So we've got that and we have the elementary charge So let's go ahead and solve for the number of electrons. So we've got a number of electrons. This is a negative sign over here, by the way, because we still have a negative sign Times the elementary charge is equal to queue, right? I'm just I just went ahead and flip the equation right here. So you have to do is move the E over to the other side. We got negative number of electrons equals Q over E. And now we've got negative 1.5 times 10 to the minus 19. I'm sorry. That's 10 negative five divided by 1.6 times 10 to the minus 19. Okay, so notice that we have a minus sign on the right side and on the left side. So those will go ahead and cancel out. We're gonna get a positive number for electrons, and that should make sense. And if you work this out, you should get 9.375 times 10 to the What is that? 13. So that's the number of electrons. So two things. This is a massive, massive number. It's like 93 trillion electrons, and that comes from the fact that electrons air so so tiny that they have a very small amount of charge. You need a lot of them to get it like a decent amount of charge. The other thing is that this number here was positive. That makes sense because electrons have a negative charge. So it worked out that we got a negative number because we had a negative charge. Anyway, let me know if you guys have any questions with this and I'll see you guys in the next video.

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Multiple Choice

How many electrons make up −1.5 × 10⁻⁵ C?

9.375×10¹³

2.4×10⁻²⁴

1.5×10¹⁴

9.375×10⁻²⁵

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Verified step by step guidance

Understand that the charge of a single electron is approximately \(-1.6 \times 10^{-19}\) C. This is a fundamental constant in physics.

To find the number of electrons, use the formula: \( n = \frac{Q}{e} \), where \( n \) is the number of electrons, \( Q \) is the total charge, and \( e \) is the charge of a single electron.

Substitute the given total charge \( Q = -1.5 \times 10^{-5} \) C and the charge of an electron \( e = -1.6 \times 10^{-19} \) C into the formula.

Calculate the division: \( n = \frac{-1.5 \times 10^{-5}}{-1.6 \times 10^{-19}} \). The negative signs will cancel each other out, leaving a positive result.

The result of this calculation will give you the number of electrons, which is a large number due to the small charge of a single electron.