+0

# yea im back

+2
173
4
+406

and i may need mathematics assistance later in the year

off-topic
Neptune  Oct 19, 2017
Sort:

#1
+394
+2

Ok, shoot, and I will see what I can do for you. (I am certified to tutor math for Kindergarten- 4th grade.) But I do enjoy higher grade math challenges!

Mr.Owl  Oct 19, 2017
#2
+406
0

"The mass of a dust particle is approximately 7.5x10^-10 kilograms and the mass of an electron is 9.1x10^-31 kilograms. Approximately how many electrons have the same mass as one dust particle?"

(X stands for multiplication in this case)

Neptune  Oct 19, 2017
#3
+2

(7.5 x 10^-10) / (9.1 x 10-31) =8.24 x 10^20 electrons in 1 mote of dust.

Guest Oct 19, 2017
#4
+91436
+4

"The mass of a dust particle is approximately 7.5x10^-10 kilograms

and the mass of an electron is 9.1x10^-31 kilograms.

Approximately how many electrons have the same mass as one dust particle?"

This is just a division problem. You want electrons are in each dust particle

So how many times 9.1x10^-31 kilograms. goes into 7.5x10^-10 kilograms

7.5x10^-10 kilograms      divided by     9.1x10^-31 kilograms

(7.5x10^-10) / (9.1x10^-31)

=(7.5/9.1) * (10^-10 / 10^-31) electrons per particle

(7.5/9.1) = 0.8241758241758242 = 8.241758241758242*10^-1

(10^-10 / 10^-31) = 10^21

$$\approx 8.24\times 10^{-1}\times 10^{21}\\ \approx 8.24\times 10^{20}\;\;\text {electons in one dust particle}$$

Melody  Oct 19, 2017

### 6 Online Users

We use cookies to personalise content and ads, to provide social media features and to analyse our traffic. We also share information about your use of our site with our social media, advertising and analytics partners.  See details