Which observer in Figure 38.1 sees the ball’s correct path? (a) the observer in the truck (b) the observer on the ground (c) both observers
Figure 38.1 Two observers watch the path of a thrown ball and obtain different results.
Answer to Problem 39.1QQ
Explanation of Solution
The laws of mechanics are same for all inertial frames. The inertial frame of the observer in truck has the inertial frame that is at moving at the velocity of the truck and the relative motion with the ball is zero so the observer in the truck sees the path of the ball move in a vertical path.
The inertial frame of the observer on the ground has the inertial frame that is at stationary and the relative motion with the ball is moving at the velocity of the truck so the observer on the ground sees the path of the ball move as a parabola.
Both the observer sees the correct path due to the validity if Newton’s laws of motion but the inertial frames are different so they see different paths of the ball.
Conclusion:
Since, both the observer sees the correct path but the inertial frames are different so they see different paths of the ball. Thus, option (c) is correct.
As the inertial frame of observer on the ground is stationary and the inertial frame of observer on the truck is moving. Thus, option (a) is incorrect.
As the inertial frames of both the observers are same due to which the path of the ball observed is different which contradicts the fact that the path seen by observer on the ground is only correct. Thus, option (b) is incorrect.
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Chapter 39 Solutions
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