Post-Assessment #34 [ENDORSED]

[Alysia Garcia 1B]

In this problem:
If an electron (mass 9.11 x 10-31 kg) has an associated wavelength of 7.28 x 10-9 m, what is its speed? Is your answer reasonable, why?
I got the answer 1x10^-5 m/s, but how would you determine if the speed is reasonable?

[KateCaldwell 1A]

I believe a speed is reasonable if it is less than the speed of light (3.00x10^8 m.s^-1). Your answer seems to be correct then because it is much smaller than the speed of light.

[Natalie Noble 1G]

This is awkward but you may want to recheck your calculations. The answer shouldn't be negative, it should be 1.00 x 10^5 m/s (if it were negative that would be an extremely slow electron). The reason 1.00 x 10^5 m/s makes sense is because the electron is moving slower that the speed of light, which makes sense (it is not possible to move faster than the speed of light).

[Maya Khoury]

I attached a picture below of me trying to find the speed for this problem but for some reason i always end up with a ridiculously large number. Can someone tell me what I'm doing wrong? I'm sure it's a stupid mistake lol

thank you !

[Chem_Mod]

Your denominator value should be more closer to 10^-40 order of magnitude not 10^-49

[Mario Reyes 1C]

I attached a picture below of me trying to find the speed for this problem but for some reason i always end up with a ridiculously large number. Can someone tell me what I'm doing wrong? I'm sure it's a stupid mistake lol

thank you !

The denominator should be 10^-39, not 10^-49