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How long in the air

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A projectile is launched off a click at an angle. The cliff is 15m high, the projectile is launched at 25 degrees above horizontal. How much time is the projectile in the air before hitting the ground?

To solve this problem, start by breaking the motion of the projectile into horizontal and vertical components. The projectile’s velocity has both an upward and forward component because it is launched at an angle. The time the projectile spends in the air depends on how long it takes for the vertical component of its motion to bring it back down to the ground after being launched off the cliff.

You need to calculate how long it takes for the projectile to rise, stop, and then fall back down past the height of the cliff. The height of the cliff (15 meters) means the projectile has to fall this distance in addition to its downward motion from the highest point it reaches. Using the initial vertical velocity and acceleration due to gravity, you can determine the total time the projectile remains in the air before it hits the ground.

Posted by grwgreg 14 days ago

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