Applications Of Derivatives Question 209
Question: The equation of motion of a stone, thrown vertically upwards is $ s=ut-6.3t^{2}, $ where the units of s and t are cm and sec. If the stone reaches at maximum height in 3 sec, then u =
Options:
A) $ 18.9cm/\sec $
B) $ 12.6cm/\sec $
C) $ 37.8cm/\sec $
D) None of these
Show Answer
Answer:
Correct Answer: C
Solution:
Velocity of particle at the maximum height $ \frac{ds}{dt}=0 $
$ \Rightarrow u-12.6t=0\Rightarrow u=12.6t=37.8,cm/s. $
BETA
