Answer:
A
Explanation:
Even if the refrigerator did not move he still used energy to try to push it it's just his energy wasnt stronger than the refrigerator's energy
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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A black hole forms when the center of a very massive star collapses in upon itself.
relation between potential difference and electric field is given as

so here we know that
d = 3 cm



So now when plates are separated to 4 cm distance carefully
the potential difference between them will change but the electric field between them will remain constant
So at distance of 4 cm also the electric field will be E = 1000 N/C
Answer:
It requires <u>1.9 seconds</u> to reach maximum height.
Explanation:
As per given question,
Initial velocity (U) =19 m/s
Final velocity (V) = 0 m/s

Maximum height = S
Time taken is "t"
<u>Calculating time taken to reach maximum height:</u>
We know that time taken to reach the maximum height is calculated by using the formula V = U + at
Substitute the given values in the above equation.
Final velocity is “0” as there is no velocity at the maximum height.



t = 1.9 seconds.
The time taken to reach maximum height is <u>1.9</u> seconds.
<u>Calculating maximum height</u>:

Solving the equation we will get the value of S

-361 = -20S
Negative sign cancel both the sides.

S = 18.05 m
Maximum height is 18.05 m .