Applications Of Derivatives Question 220
Question: The distance travelled s (in metre) by a particle in t seconds is given by, $ s=t^{3}+2t^{2}+t. $ The speed of the particle after 1 second will be
[UPSEAT 2003]
Options:
A) 8 cm/sec
B) 6 cm/sec
C) 2 cm/sec
D) None of these
Show Answer
Answer:
Correct Answer: A
Solution:
$ s=t^{3}+2t^{2}+t $
$ v=\frac{ds}{dt}=3t^{2}+4t+1 $
Speed of the particle after 1 second
$ {v_{(t=1)}}={{( \frac{ds}{dt} )}_{(t=1)}}=3\times 1^{2}+4\times 1+1=8,cm/sec. $