Waves Physics Question (1 Viewer)

[bored.of.u]

Preliminary Physics Queation,

The captain of a yacht wished to find the distance between the trough and crest of the waves that pass him to aid him during a race. He knows that the velocity of the wave is 42.3m/s and that 6 waves pass him in 3.6s. He predicts his desired distance to be 13m.

(a) Find the distance he wished to measure (trough to crest).

(b) Find the precentage error in the captains prediction.

 

[3unitz]

a)
first find the total length of the 6 wavelengths using the equation v = d/t

v = d/t
42.3 = d/3.6
d = 152.28

dividing by 6 will give us the length of 1 wavelength:

152.28/6 = 25.38

dividing by 2 will give us the length from trough to crest:

25.38/2 = 12.69m

b)
percentage error = [(13 - 12.69)/13]*100

= (0.31/13)*100

~ 2.38%

 

[bored.of.u]

a)
first find the total length of the 6 wavelengths using the equation v = d/t

v = d/t
42.3 = d/3.6
d = 152.28

dividing by 6 will give us the length of 1 wavelength:

152.28/6 = 25.38

dividing by 2 will give us the length from trough to crest:

25.38/2 = 12.69m

b)
percentage error = [(13 - 12.69)/13]*100

= (0.31/13)*100

~ 2.38%

thank you i understand now =D great working

 

[h3ll h0und]

i think there's another way....not sure if its rite though

6 waves in 3.6 seconds so
let T= period

6T= 3.6
T= 3.6/6 = 0.6
and T= 1/F (F= frequency)

so F = 1/0.6= 1.67 Hz (2 dec.)

now V=wavelength * Frequency and we noe V= 42.3 m/s and F= 1.67 Hz
so 42.3 = wavelength * 1.67Hz
so wavelength=42.3/1.67 = 25.23 m

lol i mightv done something rong...

 

[h3ll h0und]

oh wait forgot its from trough to crest so u just half it and yea

 

[bored.of.u]

i think there's another way....not sure if its rite though

6 waves in 3.6 seconds so
let T= period

6T= 3.6
T= 3.6/6 = 0.6
and T= 1/F (F= frequency)

so F = 1/0.6= 1.67 Hz (2 dec.)

now V=wavelength * Frequency and we noe V= 42.3 m/s and F= 1.67 Hz
so 42.3 = wavelength * 1.67Hz
so wavelength=42.3/1.67 = 25.23 m

lol i mightv done something rong...

its rite but dont carry on ur errors use 5/3 Hz instead of 1.67 the ans is more accurate...gr8 working 5/5 =D