Answer:
The motion of the ball relative to the ground is stationary
The motion of the ball relative to the wagon is backwards
Explanation:
To describe the motion of the ball relative to the ground, we note that
Assuming the ball is perfectly round and rotate freely, then we have
Force on the ball due to motion of the wagon = 0 N,
Then by the law of motion, an object will remain at rest when no force is applied to it
Therefore, apart from rotation of the ball, it will remain no displacement relative to the ground.
The motion of the ball relative to the wagon
Relative to the wagon, the ball appears to be moving in the opposite direction to the wagon, that is backwards.
I think the answer is D. Bicycle
The answer is Air Resistance
The dotted path is the path of the ball. it reaches it's maximum height at the top where vertical, y-velocity = 0
The initial y-velocity = 19sin(70°)
initial y-velocity = 17.85 m/s
Use one of the kinematic equations with velocity and time. No displacement because we don't want to worry about figuring that out.
v = u - gt
0 = 17.85 - 9.8t
-17.85 = -9.8t
17.85/9.8 = t
1.82 sec = t