Answer:
A) The acceleration is zero
<em>B) The total distance is 112 m</em>
Explanation:
<u>Velocity vs Time Graph</u>
It shows the behavior of the velocity as time increases. If the velocity increases, then the acceleration is positive, if the velocity decreases, the acceleration is negative, and if the velocity is constant, then the acceleration is zero.
The graph shows a horizontal line between points A and B. It means the velocity didn't change in that interval. Thus the acceleration in that zone is zero.
A. To calculate the acceleration, we use the formula:
Let's pick the extremes of the region AB: (0,8) and (12,8). The acceleration is:
This confirms the previous conclusion.
B. The distance covered by the body can be calculated as the area behind the graph. Since the velocity behaves differently after t=12 s, we'll split the total area into a rectangle and a triangle.
Area of rectangle= base*height=12 s * 8 m/s = 96 m
Area of triangle= base*height/2 = 4 s * 8 m/s /2= 16 m
The total distance is: 96 m + 16 m = 112 m
Answer:
El astrónomo alemán Johannes Kepler
Explanation:
Primera Ley:
Los planetas giran alrededor del Sol siguiendo una trayectoria elíptica. El Sol se sitúa en uno de los focos de la elipse.
La excentricidad e de una elipse es una medida de lo alejado que se encuentran los focos del centro.
Pues bien, la mayoría de las órbitas planetarias tienen un valor muy pequeño de excentricidad, es decir e ≈ 0. Esto significa que, a nivel práctico, pueden considerarse círculos descentrados.
Segunda Ley:
La recta que une el planeta con el Sol barre áreas iguales en tiempos iguales.Para que esto se cumpla, la velocidad del planeta debe aumentar a medida que se acerque al Sol. Esto sugiere la presencia de una fuerza que permite al Sol atraer los planetas, tal y como descubrió Newton años más tarde.
Tercera ley de Kepler:
La tercera ley, también conocida como armónica o de los periodos, relaciona los periodos de los planetas, es decir, lo que tardan en completar una vuelta alrededor del Sol, con sus radios medios.
Para un planeta dado, el cuadrado de su periodo orbital es proporcional al cubo de su distancia media al Sol.
Answer:
Explanation:
Assuming we have a two hot liquid like 70°C tea and 30°C water, the tea will cool down but not to 30°C but to an equilibrium temperature say 40°C
But in this case, the temperature of the chocolate will drop almost to the room temperature eventually,
The heat in the chocolate will even out into the room temperature and the room will get slightly warmer until the are both in equilibrium temperature. But you won't notice this little change but if you go out of the room, you might notice that change...
So this little fraction is not always notice, so we will still considered it as the room temperature
Answer:
<em>The engine must provide power to compensate friction</em>
Explanation:
<u>Accelerated Motion
</u>
Newton's first law states that a body will keep its speed or state of rest while no external net force is applied. Our automobile is running through a road which surface exerts a frictional force on the wheels. If we didn't use fuel, the automobile will eventually stop, because the unbalanced friction force causes deceleration. To compensate that force, we must provide power to the engine. When our speedometer shows a constant speed, the net force is zero, but the car needs to accelerate some, just to compensate the friction force.
The total acceleration keeps being zero, but the engine is actually doing work against friction.
