Imagine yourself on the surface of the Moon. In one hand you have a feather. In the other ­­ a hammer. You let go of them them at the same time. Which one hits the ground first?
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In the absence of air resistance, it is found that all bodies at the same location above the Earth fall vertically with the same acceleration. If the distance of the fall is small compared to the radius of the Earth, then the acceleration remains essentially constant throughout the descent.
This idealized motion is called free­fall and the acceleration of a freely falling body is called the acceleration due to gravity.
= 9.81 / 2
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Example 1: A Falling Stone
A stone is dropped from the top of a tall building. After 3.00 s of free fall, what is the displacement y of the stone?
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Example 2 How High Does it Go?
The referee tosses the coin up with an initial speed of 5.00m/s. In the absence of air resistance, how high does the coin go above its point of release?
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Billy, a mountain goat, is rock climbing on his favorite slope on a sunny spring morning when a rock falls down toward him from a ledge 40.0 m above. Billy ducks to avoid injury.
a. How fast is the rock traveling when it passes Billy?
b. How does this speed compare to that of a car traveling down the highway at a speed limit of 25 m/s ﴾equivalent to 55 mi/hr﴿.
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In order to open a clam it catches, a seagull will drop the clam repeatedly on to a hard surface from high in the air until the shell cracks. If a seagull flies to a height of 25 m, how long will the clam take to fall?
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The Tambora volcano on the island of Sumbawa, Indonesia has been known to throw ash into the air with a speed of 625 m/s during an eruption. a. How high could this volcanic plume have risen?
b. On Venus, where acceleration due to gravity is slightly less than on Earth, would this volcanic plume rise higher or not as high as it does on Earth?
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A unique type of a basketball is played on planet Zarth. During the game, a player flies above the basket and drops the ball in from a height of 10 m. If the ball takes 5.0 s to fall, find acceleration due to gravity on Zarth. 10