question_answer

A person sitting on the top of a tall building is dropping balls at regular intervals of one second. What are the positions of the 3rd, 4th and 5th balls respectively, when the 6th ball is being dropped?

Answer:

When the 6th ball is dropped the positions of the 3rd, 4th and 5th ball from the top are as shown in the figure the duration for the3rd ball is 3 sec, \[{{h}_{3}}=\frac{1}{2}\times gt_{3}^{2}\] \[=\frac{1}{2}\times 9.8\times 44.1\,m\] the duration for the 4th ball is 2 sec, \[{{h}_{4}}=\frac{1}{2}\times gt_{4}^{2}\] \[=\frac{1}{2}\times 9.8\times 4=19.6\,m\] the duration for the 5th ball is 1 sec, \[{{h}_{5}}\] \[=\frac{1}{2}\times g\times t_{5}^{2}=\frac{1}{2}\times 9.8\times 1=4.9\,m\]