Answer:
Explanation:
2. A compression wave, like sound, is a kind of <u>mechanical</u> wave.
3. When a wave reflects off a surface, the angle of <u>incidence</u> always equals the angle of <u>reflection</u>.
4. The wailing change of the pitch that you hear as a locomotive approaches and then recedes from you is called <u>Doppler Shift</u>.
The answer to the question is A
The angle between the two vectors is 126° 52' 11".
The given parameters;
vector A = 3.00i + 1.00j
vector B = 1.00i + 3.00j
The angle between the two vectors is calculated as follows;
The dot product of vectors A and B is calculated as;
A.B = ( 3i + 1j ) . ( 1i +3j )
= ( 3 × 1 ) + ( 1 × 3 )
= 3 + 3
= 6
The magnitude of vectors A and B is calculated as;
|A| = ![\sqrt[]{3^2 + 1^2} = \sqrt[]{10} \\](https://tex.z-dn.net/?f=%5Csqrt%5B%5D%7B3%5E2%20%2B%201%5E2%7D%20%3D%20%5Csqrt%5B%5D%7B10%7D%20%5C%5C)
|B| = ![\sqrt[]{1^2 + 3^2} = \sqrt[]{10} \\](https://tex.z-dn.net/?f=%5Csqrt%5B%5D%7B1%5E2%20%2B%203%5E2%7D%20%3D%20%5Csqrt%5B%5D%7B10%7D%20%5C%5C)
The angle between in two vectors is calculated as;
![Cos \theta = \frac{6}{\sqrt[]{10}\sqrt[]{10} } \\\\Cos \theta = \frac{6}{\ 10 }\\\\Cos \theta = 0.6\\\\\theta = cos^-^1 (0.6)\\\\\theta = 126\\](https://tex.z-dn.net/?f=Cos%20%5Ctheta%20%3D%20%5Cfrac%7B6%7D%7B%5Csqrt%5B%5D%7B10%7D%5Csqrt%5B%5D%7B10%7D%20%20%7D%20%5C%5C%5C%5CCos%20%5Ctheta%20%3D%20%5Cfrac%7B6%7D%7B%5C%2010%20%7D%5C%5C%5C%5CCos%20%5Ctheta%20%3D%200.6%5C%5C%5C%5C%5Ctheta%20%3D%20cos%5E-%5E1%20%280.6%29%5C%5C%5C%5C%5Ctheta%20%3D%20126%5C%5C)
Therefore, the angle between the two vectors is 126° 52' 11".
Learn more about vectors here:
brainly.com/question/25705666
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The two things that must exist for an electric current to be produced are:
An electric potential between two bodies and a conducting path joining the bodies.
This comes from the fact that when there is a potential difference there is an electrical field and hence a force that makes some free charges to move in the conductor. For this reason, there's an electrical current.
<h2>The correct option is (A)</h2>
Explanation:
Travels faster in solids because the particles are closer together.
The reason for the above statement is -
(i) Sound waves travel through the medium (solid, Liquid, and gas), more denser is the medium more is the speed of sound.
(ii) In solid, the particles are arranged very closely and tightly packed therefore the sound waves in solid have the fastest speed or travels fastest in comparison to liquid and gas.
(iii) Slower than solid is the travel of sound waves in liquid than in gas(least dense, particles are far apart.
