Determined to test the law of gravity for himself. A student walkd off a skusraper `180 m` high
Channel: Doubtnut
Date: 2020-07-26

Determined to test the law of gravity for himself. A student walkd off a skusraper `180 m` high stopwatch in hand, and stars his free fall (zero initial velocity). Five seconds later, Superman arrives at the scene and dives off the roop to same the student.  a. So\uerman leaves the roop with an initial speed `v_(0)` that he produces by pushing himself downward from the edge os the roof with his legs of steel. Fe then falls with the same accelerativon as any feely falling body What must the value of `v_(0)` be so that the Superman catches the student just before they reach the ground ?  b. On the same graph sketch the positions of the student and of the Superman as fuctions fo time. Take Superman`s initial speed to have the value calulated in part (a).  c. If the hdight of the skyscraper is less than some minimum value, even the Superman canot reace the sturdnt student before he hits the ground, what is this minimum height?