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To explain: The force of static friction for walking and accelerating or braking of a car.
Explanation of Solution
Consider the scenario that the when person is walking on the road, then his or her foot touches the ground that is momentarily at rest, pushes back on the ground. This scenario is matched to the newton’s third law in which if the ground is pushed forward, then it accelerates the person to move forward.
Likewise, if the car gets accelerated or at breaks then the tire at the bottom of the car is momentarily at rest. Thus, this force behind this scenario is related to static frictional force and during acceleration, the road pushes the tire in forward direction and at the time of braking, the tire pushes the road in forward direction and road pushes the tire in backward direction.
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