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How tall is the cliff if the stone was initially traveling at -15.5 m/s and hits the ground 8.5 seconds later?

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Final answer:

To find the height of the cliff, the kinematic equation is used with an initial velocity of -15.5 m/s and a time of 8.5 seconds. The calculated cliff height is approximately 221.64 meters.

Step-by-step explanation:

To calculate the height of the cliff from which a stone was initially traveling at -15.5 m/s and hits the ground 8.5 seconds later, we can use the kinematic equation:

h = v_i * t + (1/2) * g * t^2

where h is the height of the cliff, v_i is the initial velocity, t is the time, and g is the acceleration due to gravity which is approximately 9.81 m/s^2. Since the stone is initially traveling upwards, we take the initial velocity as negative for the direction of the throw against gravity. Therefore:

h = (-15.5 m/s) * (8.5 s) + (1/2) * (9.81 m/s^2) * (8.5 s)^2

h = -131.75 m + (1/2) * 9.81 m/s^2 * 72.25 s^2

h = -131.75 m + 353.38625 m

h = 221.63625 m

The height of the cliff is approximately 221.64 meters.

User Bruce Armstrong
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