Question

The motion of a particle is described by the equation x=a+bt^2where a=15cm and b=3cm. Its instantaneous velocity at time 3 sec will be

Answer 1

Answer:

Explanation:

first lets derive formula for instantaneous  velocity

the defination of instantneous velocity is velocity at praticular instant of time

means there will we know velocity=change in displacement/time

v=del theta / del t

del t is tens to 0

so you should apply limits

lim del t tends 0 del theta/ del time

del theta is also tending to 0  listen carefully i am talking about del theta

by l hosptals rule

lim del time tending 0 del theta/del time

lim del theta tending o  d deltheta /d del t  / del t/ del t

d del theta/ d del time

ds/dt

s=a+bt^2

ds/dt=2bt

v instantaneous= 2bt

=2*3*3

=18cm/s