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FromTheMoon [43]

3 years ago

12

Harry and Sally are sitting on opposite sides of a circus tent when an elephant trumpets a loud blast. If Harry experiences a so

und intensity level of 67 dB and Sally experiences only 45 dB, what is the ratio of the distance between Sally and the elephant to the distance between Harry and the elephant?

1 answer:

FromTheMoon [43]3 years ago

7 0

To solve this problem we will start from the definition of the decibels which refers to the log relationship of the intensities, mathematically each decibel of the people can be described as follows

$dB_1 = 10log(\frac{I_1}{I_o})$

$dB_2 = 10log(\frac{I_2}{I_o})$

$dB_1 - dB_2 = 10log(\frac{I_1}{I_2})$

$\frac{67-45}{10} = log(\frac{I_1}{I_2})$

$log(\frac{I_1}{I_2}) = \frac{11}{5}$

For properties of the logarithm then we have that,

$\frac{I_1}{I_2} = 10^{11/5}$

$\frac{I_1}{I_2} = 158.48$

We have the relation

$\frac{r_2^2}{r_1^2} = 158.48$

$\frac{r_2}{r_1} = \sqrt{158.48}$

$\frac{r_2}{r_1} = 12.58$

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Answer:

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use Right Hand Rule which will give the direction and by using his the direction will come towards negative y axis.

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and magnitude should be same as magnectic force and also direcion of electric force depend on the direction of elecric field when charge is positive because electric force $F_E = qE$

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4 years ago

A 1900kg airplane is flying at an altitude of 510 above the ground. What is the gravitational potential energy in Joules?

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Gravitational potential energy, GPE is the energy possessed by the moving plane since it moves against gravity.

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