Shopping Cart Physics Explained: Action and Reaction Forces

What are action and reaction forces in the context of pushing a shopping cart?

Which pair of forces represents action and reaction forces in this scenario?

Answer:

The pair of action and reaction forces in this scenario is the downwards force that the cart exerts on the ground and the support force of the ground on the cart.

When you are pushing a shopping cart forward in a parking lot, there are different forces at play that demonstrate the concept of action and reaction forces. In this scenario, the action and reaction forces can be observed between the shopping cart and the ground.

As you exert a force on the shopping cart by pushing it forward, your hand applies a force to move the cart. According to Newton's third law of motion, for every action, there is an equal and opposite reaction. Therefore, the cart exerts an equal and opposite force back on your hand. This interaction represents the concept of action and reaction forces.

Now, let's consider the forces acting on the shopping cart when it is in contact with the ground. The cart experiences the force of gravity pulling it downward towards the Earth. In response to this gravitational force, the ground exerts an equal and opposite force upwards on the cart. This upward force from the ground is known as the support force. The support force counteracts the gravitational force and prevents the cart from falling through the ground.

Therefore, the pair of action and reaction forces in this scenario is the downwards force that the cart exerts on the ground and the support force of the ground on the cart. These forces have equal magnitudes but act in opposite directions, exemplifying Newton's third law of motion.

By understanding the interplay of forces in simple everyday scenarios like pushing a shopping cart, we can grasp the fundamental principles of physics at work around us. Action and reaction forces are essential concepts in physics that govern the motion and interactions of objects in our physical world.