A person wearing roller skates stands facing a solid concrete wall. When they push forward against the wall with their hands, they immediately roll backward. According to Newton's Third Law of Motion, which of the following best explains why the person rolls backward?
- AThe person's inertia resists their forward push, which creates a backward force that moves them away from the wall.
- The wall exerts a reaction force on the person that is equal in magnitude and opposite in direction to the person's push.Answer
- CBecause the person has less mass than the wall, they experience a greater reaction force than they originally applied.
- DThe person moves backward because their body weight is much less than the overall weight of the concrete wall.
Answer
The wall exerts a reaction force on the person that is equal in magnitude and opposite in direction to the person's push.
According to Newton's Third Law, forces always occur in pairs. When the person applies an action force forward onto the wall, the wall simultaneously applies an equal reaction force backward onto the person. This backward force acts on the person and causes them to roll backward on their low-friction skates.
Step-by-Step Solution
Key Concept
Newton's Third Law states that when one object exerts a force on a second object, the second object simultaneously exerts an equal and opposite force on the first object.
Estimated Time:45s