Well, depending on which way you are pushing, it could be one of three forces.
If you are pushing along a table, then it is friction that is preventing the box from moving (or more accurately, static friction).
If you are pushing the box down into the table, then it is the normal force that is at work.
If you are pushing into the air, then it is gravity.
The force that is pushing back and keeping the box from moving is friction, which is the resistance force between the surfaces of the box and the surface it rests on.
Buoyancy= ρgV, where ρ is the density of the liquid, g is the acceleration due to gravity, and V is the volume of water displaced.
frictional force
inersia
An example of output force is the force exerted by a person lifting a box off the ground. When the person applies a force to lift the box, the box applies an equal and opposite force (output force) back on the person.
The upward force exerted on you while standing on the ground is equal to your weight, as determined by the force of gravity pulling you toward the Earth. This force does not lift you up because it is balanced by the force exerted by the ground pushing back on you (normal force), keeping you in equilibrium and preventing you from accelerating upward.
The answer is reaction. A simple example is you standing on the ground. You are not moving or accelerating (in our reference frame). You are pushing down against the ground with a force (the action) equal to your weight. The ground pushes back up (opposite direction) with an equal force (the reaction force).
Force A is Gary's weight pulling him downward towards the ground. Force B is the reaction force from the ground pushing back up against Gary's feet as he rests on the ground.
As you push off the ground with your skates, the action force propels you forward. The reaction force that keeps you moving comes from the ground pushing back against your skates in the opposite direction. This interaction allows you to maintain your momentum and continue skating.
static friction
gravity
The action is the finger pushing the nose. The reaction is the nose pushing back on the finger.
he is holding a stack of books on his back but he is not moving
If there was no friction, your foot would simply slide back as you tried to take steps, and you would go nowhere. In order for something to move, it has to have a force moving it. That force has to have leverage, or friction. For the force pushing a person forward, there is an equal force pushing backward on the ground or floor. You can observe this by placing round pencils under a board, stand on it, and try to step off in the perpendicular direction : the board will roll backward as you step forward.
Simple answer: yes In order for you to stand, talk, move... ect objects must exert a force on you. For example if you are standing on the ground, the ground has to be pushing back at you, or you would just fall through. If an object doesn't exert the same force you exert on it, then you are moving the object.
1. Inertia 2. Friction 3. A force when you move your pen or hand
When an airplane is motionless on the tarmac, discounting any winds, there are two primary forces acting on it. First is the force of gravity pushing downwards, and secondly, there is the reactionary force pushing back upwards.
When catching a ball, the action force is the force applied by the ball on your hand. The reaction force is the equal and opposite force applied by your hand on the ball. These forces are part of Newton's Third Law of Motion.
The answer is reaction. A simple example is you standing on the ground. You are not moving or accelerating (in our reference frame). You are pushing down against the ground with a force (the action) equal to your weight. The ground pushes back up (opposite direction) with an equal force (the reaction force).
Possibly water resistance (drag)
When you blow air into a balloon, the action force is the force exerted by you on the balloon to push air inside it. The reaction force is the force exerted by the balloon on you in the opposite direction, due to Newton's third law of motion stating that for every action, there is an equal and opposite reaction.