A small rock bounces off the windshield of a moving car and experiences a large change in velocity. How does the car’s momentum change?(1 point)
Responses
It has a change in momentum greater than that of the rock, in the opposite direction.
It has a change in momentum greater than that of the rock, in the opposite direction.
It does not change.
It does not change.
It has a change in momentum equal to that of the rock, in the opposite direction.
It has a change in momentum equal to that of the rock, in the opposite direction.
It has a much smaller change in momentum than that of the rock, in the opposite direction.
It has a change in momentum equal to that of the rock, in the opposite direction.
The correct answer is: It has a change in momentum equal to that of the rock, in the opposite direction.
The correct response is: It has a change in momentum equal to that of the rock, in the opposite direction.
Explanation:
To find the change in momentum, we need to use the principle of conservation of momentum. The total momentum before the collision is equal to the total momentum after the collision. In this case, the only objects involved are the car and the rock.
Before the rock hits the windshield, both the car and the rock have their own momenta. Let's call the momentum of the rock 'p1' and the momentum of the car 'p2'. Since the rock is initially at rest, its momentum is zero (p1 = 0). The car, on the other hand, is in motion, so its momentum is non-zero (p2 ≠ 0).
When the rock bounces off the windshield, it gains momentum in the opposite direction of its initial motion. Let's call the change in momentum of the rock 'Δp1'. Since the rock is bouncing off, its change in momentum will be negative (Δp1 < 0).
According to the principle of conservation of momentum, the total momentum after the collision must be equal to the total momentum before the collision. The total momentum after the collision is the sum of the momenta of the car and the rock, which can be written as p2 + Δp1.
Therefore, the change in momentum of the car, which we'll call 'Δp2', can be found by rearranging the equation: p2 + Δp1 = p2 + Δp2. Since the car and the rock are the only objects involved in the collision, the change in momentum of the car will be equal in magnitude but opposite in direction to the change in momentum of the rock (Δp2 = -Δp1).
So, the car's change in momentum is equal to that of the rock, in the opposite direction.