In the cabin of a jetliner that cruises at 600km/h, a pillow from an overhead rack falls into your lap below since the jetliner is moving so fast, why doesn't the pillow slam into the rear of the compartment when it drops? What is the horizontal speed of the pillow relative to the
ground? Relative to you inside the jetliner
The jetliner is moving at 600 km/hr. You are moving at 600 km/hr. The pillow and everything else in the cabin is moving at 600 km/hr. The speed relative to the ground is 600 km/hr for the pillow. The speed of the pillow relative to your lap is zero (because both of you are moving at the same speed).
Well, I guess that pillow is in for a wild ride! The reason it doesn't slam into the rear of the compartment is because of the principle of inertia. Just like how you stay in your seat when the jetliner takes off, the pillow wants to keep moving at the same speed and direction as the plane.
As for the horizontal speed of the pillow relative to the ground, it's the same as the jetliner's speed, which is 600km/h. However, relative to you inside the jetliner, it appears to be stationary since you're both moving at the same speed. So, you could say it's napping along with you onboard!
The pillow does not slam into the rear of the compartment because it retains the forward speed of the jetliner while falling due to the principle of inertia.
The horizontal speed of the pillow relative to the ground is also 600 km/h, since it maintains the same speed as the jetliner.
Relative to you inside the jetliner, the horizontal speed of the pillow is zero. This is because you and the pillow are both moving at the same speed and direction inside the jetliner, so it appears to be stationary with respect to you.
The reason the pillow doesn't slam into the rear of the compartment when it drops is due to a principle called the principle of inertia or Newton's first law of motion. According to this principle, an object in motion tends to stay in motion unless acted upon by an external force.
When the pillow falls from the overhead rack, it was already moving at the same horizontal speed as the jetliner, which is 600 km/h. Since the pillow was already moving at this speed, it will continue to move at that speed horizontally even after it falls.
Relative to the ground, the horizontal speed of the pillow remains the same as that of the jetliner, which is 600 km/h. This means that whether it's inside the jetliner or on the ground, the pillow's horizontal speed remains constant.
However, relative to you inside the jetliner, the horizontal speed of the pillow appears to be zero. This is because both you and the pillow are moving at the same horizontal speed within the confines of the jetliner. So, from your perspective, the pillow doesn't seem to have any horizontal motion.
In summary:
- Relative to the ground, the horizontal speed of the pillow is 600 km/h, the same as that of the jetliner.
- Relative to you inside the jetliner, the horizontal speed of the pillow appears to be zero because you and the pillow are moving at the same speed within the jetliner.