Question

What is the speed of a wave with a frequency of 2 Hz and a wavelength of 87 m?

0.023 m/s
43.5 m/s
89 m/s
174 m/s

Answer 1

I keep getting the wroung the answer

Answer 2

What do you keep getting?

Answer 3

A negative

Answer 4

The speed of a wave is given by where is the wavelength of the wave is the frequency of this problem, we have a wave of wavelength and frequency.

Answer 5

Sorry if it's hard to read, I messed all the time.

Answer 6

It's fine

Answer 7

So we find for the speed?

Answer 8

The first one and the second one can go because there the slowest, and the human eye would be able to see them.
- The second one would have to be seen with a telescope, to your eye. - Do you get what I mean?

Answer 9

yes

Answer 10

ok

Answer 11

89 m/s wouldn't be seen by?

Answer 12

the human eye

Answer 13

and

Answer 14

small tele's

Answer 15

A telescope

Answer 16

*Small telescope*

Answer 17

oh

Answer 18

So, what do you get?

Answer 19

174 m/s? or 89 m/2?

Answer 20

Um.....is it 174 m/s

Answer 21

Good job. :)

Answer 22

Thank you :3

Answer 23

@QuestionCoveBot

Answer 24

k

Answer 25

@QuestionCoveBot is correct here but you can't reason through the question by seeing if it's visible to the naked eye or you're likely to get other questions wrong...you're gonna have to do the math here.

\[v=\lambda f\]
Here you are given \(\lambda=87~m,~~f=2~Hz\)
So you can plug that in
Remember that \(1~Hz=1~s^{-1}\), so your final unit would still be m/s as indicated in the answer choices.
Plugging that in...
\[v=(87~m)(2~s^{-1})\]
\[=174~m/s\]