Timeline for What force causes the ball to move up?
Current License: CC BY-SA 3.0
7 events
| when toggle format | what | by | license | comment | |
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| Jan 1, 2016 at 20:04 | comment | added | user98038 | I think that there might be a little misunderstanding here. If I throw a ball vertically upwards with an initially velocity ,then given the fact that the only force acting is gravity ,this doesn't mean that the ball will instantly move downwards.We add vectors as force with force and velocity with velocity.In a moment velocity and force can have different directions. | |
| Jan 1, 2016 at 19:10 | comment | added | user5539357 | To make the ground exert greater force on the ball, the ball itself needs to exert a greater force on the ground, right? And the only such force I can think of would be associated with inertia (centrifugal force acting on the ground). The problem is, centrifugal force appears only in non-inertial reference frame. | |
| Jan 1, 2016 at 17:44 | comment | added | Floris | For the same reason that when a ball hits a surface it exerts a force greater than its weight - the surface is moving towards the ball. | |
| Jan 1, 2016 at 17:05 | comment | added | user5539357 | When the ball is at rest, the normal force (the force exerted on the ball by surface it's situated on) is 'at most' equal to $mg$ - its weight (it's obviously smaller when the surface isn't parallel to the ground). The interesting question is why the normal force is actually greater in this case. | |
| Jan 1, 2016 at 16:53 | comment | added | Floris | Yes you probably should edit that into your question | |
| Jan 1, 2016 at 16:52 | comment | added | user5539357 | The speed doesn't change until the ball reaches the red arrow (I should have added that). | |
| Jan 1, 2016 at 16:43 | history | answered | Floris | CC BY-SA 3.0 |