Part A You are part of a searchand rescue mission that has b

Part A You are part of a searchand- rescue mission that has been called out to look for a lost explorer You\'ve found the missing explorer, but you\'re separated from him by a 200-m-high cliff and a 30-m-wide raging river. To save his life, you need to get a 4.0 kg package of emergency supplies across the river. Unfortunately, you What minimum speed must the rocket have just before impact in order to save the explorer\'s lit Express your answer to two significant figures and include the appropriate units Figure 1 ofl Package Submit My Answers Give Up Incorrect, Try Again; 2 attempts remaining 200 m Pro Explorer 30 m

Solution

Time taken by the package to reach the explorer if launched horizontally is same as the time taken by the package if it is dropped from that height. This is because there is no vertical component of velocity initially for both the cases.

Using the equation h = ut + 1/2 gt², and setting the initial velocity, u = 0,
Time taken by the package to reach the bottom, t = SQRT[2h/g]
= SQRT[2 x 200 / 9.81]
= 6.386 s

Horizontal velocity x time = Horizontal distance
Horizontal velocity = Horizontal distance / time
= 30 / 6.386
= 4.7 m/s