a gardener pushes a wheelbarrow.
according to Newton's third law the barrow's reaction force on the gardener is the exact opposite of her force on the barrow. a bystander concludes the gardener and barrow will not move because they push equally against each other. how can i explain to him why the gardener and barrow will move?thx.
The net force is zero. So there is no acceleration. What does that have to do with Newtons first law?
The net force is zero. So there is no acceleration. What does that have to do with Newtons first law?
i think friction is cool
Newton's first law of motion, also known as the law of inertia, states that an object at rest will stay at rest, and an object in motion will stay in motion with a constant velocity, unless acted upon by an external force.
In this case, the gardener and the wheelbarrow are initially at rest, but the gardener exerts a force on the wheelbarrow to push it. According to Newton's third law, the wheelbarrow will exert an equal and opposite force on the gardener. While these forces are equal in magnitude and opposite in direction, they do not cancel each other out.
As the gardener pushes the wheelbarrow, the force she exerts causes the wheelbarrow to move forward. Due to Newton's first law, the wheelbarrow would like to stay in motion with its constant velocity. However, the reaction force from the wheelbarrow on the gardener does not stop the wheelbarrow from moving. Instead, it provides the necessary force to overcome inertia and allow both the gardener and the wheelbarrow to move forward together.
Therefore, it is incorrect to conclude that the gardener and the wheelbarrow will not move because they push equally against each other. The gardener and the wheelbarrow will move because the gardener's force overcomes the wheelbarrow's inertia, and they will continue moving as long as an external force is continuously applied to them.
To explain to the bystander why the gardener and the wheelbarrow will move, you can use Newton's first law of motion, also known as the law of inertia.
Newton's first law states that an object at rest will remain at rest, and an object in motion will continue in motion at a constant velocity unless acted upon by an external force.
In this situation, when the gardener pushes the wheelbarrow, she exerts a force on the wheelbarrow, and according to Newton's third law, the wheelbarrow exerts an equal and opposite force on the gardener. These forces are action-reaction pairs.
However, since the wheelbarrow is initially at rest, the gardener's force overcomes the initial static friction between the wheelbarrow and the ground. Once the static friction is overcome, the wheelbarrow starts moving. This movement implies that the net force on the wheelbarrow is not zero.
According to Newton's first law, once the wheelbarrow is in motion, it will tend to continue moving at a constant velocity in the absence of any external force. Hence, the gardener's force on the wheelbarrow sets it in motion, and due to inertia, the wheelbarrow will continue to move even after the gardener stops pushing.
In conclusion, the reason the gardener and the wheelbarrow will move is that the initial force applied by the gardener overcomes the static friction between the wheelbarrow and the ground, setting it in motion. Once in motion, the wheelbarrow will continue moving due to its inertia, in accordance with Newton's first law.