Answer:
B
Explanation:
You always want to test as many samples as possible
Explanation:
Noise is sound with a continuous structure. Music is composed of sounds with a fundamental frequency and overtones. Noise is composed of sounds with frequencies that range continuously in value from as low as you can hear to as high as you can hear — not necessarily at equal intensity, however.
<u>Answer:</u>
<em>The initial distance between the trains is 1450 m.
</em>
<u>Explanation:</u>
In the question two trains are of equal length 400 m and moves at a uniform speed of 72 km/h. train A is moving ahead of train B. If the train B has to overtake train A it should accelerate.
Train B’s acceleration is 
and it accelerated for 50 seconds.
<em>
</em>
<em>t=50 s
</em>
<em>initial speed u=72km/h
</em>
<em>we have to convert this speed into m/s </em>
<em>
</em>
<em>Distance covered in accelerating phase 
</em>
<em>
</em>
<em>
</em>
If a train is just behind another, the distance covered by the train located behind during overtaking phase will be equal to the sum of the lengths of the trains.
<em>Here length of train A+length of train 
</em>
<em>Hence the initial distance between the trains = 
</em>
Answer:
La fuerza que será necesaria aplicar a un cuerpo de 20kg de masa para imprimirle una aceleración a=4m/s² es 80 N.
Explanation:
La segunda ley de Newton, llamada ley fundamental o principio fundamental de la dinámica, plantea que un cuerpo se acelera si se le aplica una fuerza.
De esta manera, esta ley establece que las aceleraciones que experimenta un cuerpo son proporcionales a las fuerzas que recibe. Dicho de otra forma, la aceleración de un cuerpo es proporcional a la fuerza neta que se le aplica. Cuanto mayor es la fuerza que se le aplica a un objeto con una masa dada, mayor será su aceleración.
La segunda Ley de Newton se expresa matemáticamente como:
F = m*a
Donde:
-
F es la fuerza neta. Se expresa en Newton (N)
- m es la masa del cuerpo. Se expresa en kilogramos (Kg.).
- a es la aceleración que adquiere el cuerpo. Se expresa en metros sobre segundo al cuadrado (m/s²).
En este caso:
Reemplazando:
F= 20 kg* 4 m/s²
Resolviendo:
F= 80 N
<u><em>La fuerza que será necesaria aplicar a un cuerpo de 20kg de masa para imprimirle una aceleración a=4m/s² es 80 N.</em></u>
