Explanation:
From the given figure,
Mass of ball A is 4.9 kg and its initial speed is 8 m/s.
Mass of ball B is 1.9 kg and its initial speed is 14 m/s.
Mass of ball C is 0.7 kg and its initial speed is 2 m/s.
We need to find the final speed of the balls 1 s after being thrown. They all are thrown upward under the action of gravity. The equation of motion is : v = u -gt, g = 10 m/s²
For ball A,
v = 8-10(1) = = -2 m/s (downward)
For B,
v = 14-10(1) = 4 m/s (upward)
For C,
v = 2-10(1) = -8 m/s (downward)
It means the ranking is B>A>C i.e. the speed of ball B is the most and that of C is least.
All the balls are moving under the action of gravity. It would mean that the acceleration for all balls is same i.e. 10 m/s²
Answer:

Explanation:
As we know by work energy theorem that work done by all forces is equal to change in kinetic energy
So we know that
![W_f + W_g = \frac{1]{2}mv_f^2 - \frac{1}{2}mv_i^2](https://tex.z-dn.net/?f=W_f%20%2B%20W_g%20%3D%20%5Cfrac%7B1%5D%7B2%7Dmv_f%5E2%20-%20%5Cfrac%7B1%7D%7B2%7Dmv_i%5E2)
so we know that




now we have



Responder:
<h2>64 Julios
</h2>
Explicación:
La energía cinética se expresa mediante la fórmula KE = 1 / 2mv² donde;
m es la masa del cuerpo
v es la velocidad del objeto
Dado que el cuerpo se mueve horizontalmente con v = 4 m / sy después de un período de tiempo se mueve con v = 20 m / s, entonces la variación en la velocidad será de 20 m / s - 4 m / s = 16 m / s.
Parámetros dados
masa del objeto m = 0,5 kg
Variación de velocidad = 16 m / s
Variación de la energía cinética = 1/2 * 0,5 * 16²
Variación de la energía cinética = 1/2 * 0,5 * 256
Variación de la energía cinética = 0,5 * 128
<em>Variación de la energía cinética = 64 Julios</em>
The height of the wood is 5 cm. The length is 2 cm and the width its 3 cm. Multiply that and you get 6 cm. The Volume formula is Length times Width times Height. 6 cm times 5 cm makes 30 cm, which is your width.