Question

Janet jumps off a diving platform with a horizontal velocity of 2.12 m/s & lands in the water 1.7 s later.
How high is the platform?The acceleration of gravity is 9.8 m/s2

Answer 1

We need only vertical velocity and it's equal to zero. So, we will have:

$$h = v _ {0} \cdot t + \frac {g \cdot t ^ {2}}{2} = | v _ {0} = 0 | = \frac {g \cdot t ^ {2}}{2} = \frac {9.8 \cdot 1.7 ^ {2}}{2} = 14.161 \mathrm {m}.$$

Answer: 14.161 meters.