Respuesta :
Answer:
B
Explanation:
Solution:-
- Take a coordinate system as follows:
x: Directed along the ground
y: Directed vertical to ground
- We will assume that the initial vertical and horizontal non-zeroes velocities are given as follows:
[tex]v_x_i = v_o_x\\\\v_y_i = v_o_y\\[/tex]
- After a ball is thrown it continues a path of parabolic projectile. The motion of the ball can be analyzed in each coordinate system. We will assume that effects of air-resistance are negligible.
- Therefore, only gravity acts on the ball in the vertical direction. We can use kinematic equation of motions to determine the velocity of ball in either ( x-y ) direction at any instant of time ( t ).
- Use first kinematic equation of motion in both x and y directions.
[tex]v_x_f = v_o_x + a_x*t\\\\v_y_f = v_o_y + a_y*t\\[/tex]
- The accelerations ( ax and ay ) in the direction of each axis are to be determined. We know that the gravity acceleration ( g ) acts in vertical direction or along y-axis ( ay ) and always directed downwards while velocity is directed up. Since, we neglected the effects of air-resistance there is no acceleration in the x-direction ( ax = 0 ) .
[tex]v_x_f = v_o_x\\\\v_y_f = v_o_y - gt\\[/tex]
- We see that the horizontal velocity of the ball ( vxf ) at any point in time remains equal to the initial horizontal velocity; hence, it is constant throughout the journey.
- However, the velocity of the ball in vertical direction( vyf ) is changing for every unit of time ( t ) under the influence of gravitational acceleration. Hence, it is not constant throughout the journey
