Answer:
1.5106 cm
Explanation:
The beat frequency is equal to the absolute value of the difference between the frequencies of the two signals:
![f_B = |f_1 - f_2|](https://tex.z-dn.net/?f=f_B%20%3D%20%7Cf_1%20-%20f_2%7C)
using the wave equation, we can re-write each frequency as
![f=\frac{c}{\lambda}](https://tex.z-dn.net/?f=f%3D%5Cfrac%7Bc%7D%7B%5Clambda%7D)
where c is the speed of light and
is the wavelength. Therefore,
![f_B = |\frac{c}{\lambda_1}-\frac{c}{\lambda_2}|](https://tex.z-dn.net/?f=f_B%20%3D%20%7C%5Cfrac%7Bc%7D%7B%5Clambda_1%7D-%5Cfrac%7Bc%7D%7B%5Clambda_2%7D%7C)
where:
is the beat frequency
is the wavelength of the first generator
is the wavelength of the second generator
We also know that the second generator emits the longer wavelength, so we already know that the term inside the module is positive. Therefore, we can now solve for
:
![f_B = c(\frac{1}{\lambda_1}-\frac{1}{\lambda_2})\\\lambda_2=(\frac{1}{\lambda_1}-\frac{f_B}{c})^{-1}=(\frac{1}{0.015}-\frac{140\cdot 10^6}{3\cdot 10^8})^{-1}=0.015106 m = 1.5106 cm](https://tex.z-dn.net/?f=f_B%20%3D%20c%28%5Cfrac%7B1%7D%7B%5Clambda_1%7D-%5Cfrac%7B1%7D%7B%5Clambda_2%7D%29%5C%5C%5Clambda_2%3D%28%5Cfrac%7B1%7D%7B%5Clambda_1%7D-%5Cfrac%7Bf_B%7D%7Bc%7D%29%5E%7B-1%7D%3D%28%5Cfrac%7B1%7D%7B0.015%7D-%5Cfrac%7B140%5Ccdot%2010%5E6%7D%7B3%5Ccdot%2010%5E8%7D%29%5E%7B-1%7D%3D0.015106%20m%20%3D%201.5106%20cm)
Answer: Protons are positively charged particles
Explanation:
A hand is burned when touching a pot handle
To develop this problem we will apply the concepts related to the kinematic equations of motion, specifically that of acceleration. Acceleration can be defined as the change of speed in an instant of time, mathematically this is
![\vec{a} = \frac{\vec{v_2}-\vec{v_1}}{\Delta t}](https://tex.z-dn.net/?f=%5Cvec%7Ba%7D%20%3D%20%5Cfrac%7B%5Cvec%7Bv_2%7D-%5Cvec%7Bv_1%7D%7D%7B%5CDelta%20t%7D)
If a mobile is decreasing its speed (it is slowing down), then its acceleration is in the opposite direction to the movement. This would imply that the acceleration vector is opposite to the velocity vector.
Therefore the correct answer is B.
Usually, the forces that start the oscillation of buildings are the wind and microearthquakes.