Answer:
B) is downward
Explanation:
The acceleration is always downward, because it is the gravitational acceleration.
When the ball is going up the acceleration is opposing the movement, and when the ball is going down the velocity has the same direction as the acceleration
Answer:
D) Vertically.
Explanation:
A free body diagram is used to represent all the forces acting in a body. forces like, the force of gravity as a result of the gravitational interaction between the object and the Earth (W), the frictional force opposite to the movement of the object (
), the normal force due to the plane and the object (N) and the force applied to start the movement in a particular direction (F).
As is show in the free body diagram of the system, W, which is the weight of the body as a consequence of the gravitational force, is at an angle 
below the inclined plane. that angle between the plane and the x axis is the same that the one of the inclined plane with respect to the horizontal, Since its sides are perpendicular.
Notice how W goes always in the direction to the center of mass of Earth in a vertical path (For comparison see figure (a) and (b)).
Tenemos.
Masa de la mesa = 20kg
Masa encima = 10kg
Masa total = 30kg
Area de cada pata = 20cm² = 20cm² * 1/10000cm² * 1m² =0,002m²
Presió(P)n que se ejerce sobre cada pata.
P =F/A
P = Masa por gravedad/A Masa = 30kg Gravedad =9,8m/s²
P =(30kg * 9,8m/s²)/0,002m²
P = 294kg * m/s²/0,002m² Pero kg *m/s² = Nw
P = 294Nw0,002m²
P = 147000 Nw/m² Pero Nw/m² = pa
p =1,47 * 10⁵ pa
Respuesta.
La presión que se ejerce sobre cada pata es de 1,47 * 10⁵pa
<span>You should deflect the
ball in order to maximize your speed on the skateboard.
Since this creates a larger impulse, you want to deflect the ball. Splitting it
up into catching and throwing the ball may by something you can think of deflecting
the ball. First, you need to catch the ball, which in turn would push you
forward with some speed. (The speed we are talking about should obviously be
equal to option A, where you catch the ball). Now, throw the ball back to him
since these two processes are equal to deflecting the ball. Throwing a mass away
from you would cause or enable you to move even fast.</span>
Sample Response: "No, steel and carbon would not form metallic bonds because metallic bonds only form between metals. Iron is a metal, but carbon is not."
