Given data:
Initial velocity u = 49m/s
Final speed v at maximum height = 0
Acceleration due to earth gravity g = -9.8 m/s2 (thus negative as ball is thrown up).
By third equation of motion,
v2 = u2 - 2gs
Substitute all the values in the above equation
\( 0=(49)^2-2\times 9.8 \times s\)
\(S = \frac{(49)^2}{2 \times 9.8}\)
s = 122.5m
Total time T = Time to ascend (Ta) + Time to descend(Td)
V = u - gt
\(0 = 49 - 9.8 \times Ta\)
Ta = (49/9.8) = 5s
Also, Td 5s
Therefore T = Ta + Td
T = 5 + 5
T = 10s
Answered by Vishal kumar | 2 years ago
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