Answer:
Al llegar a su equilibrio térmico ambas barran tendrán una temperatura de 53 grados centígrados.
Explanation:
Dado que una barra de aluminio que está a 78 grados centígrados entra en contacto con una barra de cobre de la misma longitud y área que esta a 28 grados centígrados, y posteriormente se lleva acabo la transferencia de energía entre ambas barras llegando a su equilibrio térmico, para determinar la temperatura a la que ambas barras llegarán se debe realizar el siguiente cálculo:
(78 + 28) / 2 = X
106 / 2 = X
53 = X
Por lo tanto, al llegar a su equilibrio térmico ambas barran tendrán una temperatura de 53 grados centígrados.
Answer:
18.03 N
Explanation:
From the fiqure below,
Using parallelogram law of vector
R² = 15²+5²-2×5×15cos(180-60)
R² = 225+25-150cos120°
R² = 250-150(-0.5)
R² = 250+75
R² = 325
R = √325
R = 18.03 N
Hence the resultant force of the object is 18.03 N
Answer:
the answer is B
Explanation:
The atomic mass of an atom is the sum of the protons plus neutrons it has.
Answer:
The thrown rock will strike the ground 
earlier than the dropped rock.
Explanation:
<u>Known Data</u>
, it is negative as is directed downward
<u>Time of the dropped Rock</u>
We can use 
, to find the total time of fall, so 
, then clearing for 
.
![t_{D}=\sqrt[2]{\frac{300m}{4.9m/s^{2}}} =\sqrt[2]{61.22s^{2}} =7.82s](https://tex.z-dn.net/?f=t_%7BD%7D%3D%5Csqrt%5B2%5D%7B%5Cfrac%7B300m%7D%7B4.9m%2Fs%5E%7B2%7D%7D%7D%20%3D%5Csqrt%5B2%5D%7B61.22s%5E%7B2%7D%7D%20%3D7.82s)
<u>Time of the Thrown Rock</u>
We can use , to find the total time of fall, so 
, then, 
, as it is a second-grade polynomial, we find that its positive root is 
Finally, we can find how much earlier does the thrown rock strike the ground, so 
"<span>An atom is the smallest unit of matter and an element is a pure substance that is made of identical atoms" is correct. Although atoms can be broken down further now, it still take a whole atom to make an element. </span>
