Solving Physics Vectors: Car Velocity and Ball Velocity Relative to Kids/Road

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To solve the physics problem, the velocity of the ball relative to the children is calculated by adding the car's speed (20 m/s) to the ball's speed (2 m/s), resulting in 22 m/s. For the velocity of the ball relative to the road, the same calculation applies, yielding the same result of 22 m/s. The discussion emphasizes understanding the concept of "relative to," indicating that the reference point (children or road) is considered stationary for the calculations. Clarification is provided that all motion is assessed based on the chosen reference frame. This approach helps in accurately determining relative velocities in physics problems.
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Homework Statement


A child, sitting in the backseat of a car traveling at 20 m/s, throws a ball at 2 m/s to her brother who is siting in the front seat.
a. what is the velocity of the ball relative to the children?
b. what is the velocity of the ball relative to the road?

V of car = 20m/s
V of ball = 2 m/s

Homework Equations



Adding or subtracting?

The Attempt at a Solution


a. 20 m/s + 2m/s = 22 m/s
b. 20 m/s + 2m/s = 22 m/s

??
I am really confused
 
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When the problem states "relative to", it means pretending that the object, say the children or the road, is not moving. All the motion in the problem is based on everything else "moving" relative to the object you are using as your reference.

Does this make sense?
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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