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3 years ago

If the world population grows at a constant rate of 1.8% per annum, how many years will it take to double? A) 17.7 years

Physics

1 answer:

AleksandrR [38]3 years ago

4 0

Answer:

after 38.8 years it will double

correct option is D 38.8 years

Explanation:

given data

population grows rate = 1.8%

to find out

how many years will it take to double

solution

we consider here initial population is x

so after 1 year population will be = (100% + 1.8% ) x = 1.018 x

and after n year population will be = $1.018^{n} x$

so it will double

2x = $1.018^{n} x$

take log both side

log 2 = n log (1.018)

n = $\frac{log2}{log1.018}$

n = 38.853

so after 38.8 years it will double

correct option is D 38.8 years

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Answer:

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b) 9.089 m

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3 years ago

One string of a certain musical instrument is 70.0 cm long and has a mass of 8.79 g . It is being played in a room where the spe

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To solve this problem we will apply the concepts of linear mass density, and the expression of the wavelength with which we can find the frequency of the string. With these values it will be possible to find the voltage value. Later we will apply concepts related to harmonic waves in order to find the fundamental frequency.

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Now the velocity of the wave would be

$v = f_s \lambda$

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$v^2 = \frac{T}{\mu}$

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