Question

The position of an object at time t is given by s(t) = -2 - 6t. Find the instantaneous velocity at t = 2 by finding the derivative.

Answer 1

@SithsAndGiggles

Answer 2

v=-6

Answer 3

v=d(s(t))/dt

Answer 4

um..?

Answer 5

the velocity is the derivate of position equation

Answer 6

so v=d(-2-6(2))/d(2)?

Answer 7

first derivate, then plug in values

Answer 8

you cant derivate, in relation to a number, you want to know the variation of position in respect to time.

Answer 9

which is the velocity.

Answer 10

do you know what is a derivate?

Answer 11

im working on it

Answer 12

-34

Answer 13

still have no clue :(

Answer 14

see as h approx to zero that limit give the instantaneous velocity: deltas/deltat

Answer 15

that limit is the derivate.

Answer 16

but I have to show step by step how to do this and I have no clue

Answer 17

do you agree that limit is the instantaneous velocity, you see why?

Answer 18

honestly...what you showed me looks like a whole other language...

Answer 19

what is velocity?

Answer 20

the speed of something in a given direction.

Answer 21

how do you measure speed?

Answer 22

seconds?

Answer 23

in a pratical way

Answer 24

distance over time?

Answer 25

yes

Answer 26

that equation give you two position right?

Answer 27

sure

Answer 28

then if you look at a postition in a instant (t), and then you look again at an instant(t+h), the diferente between this two instants isn't the distance?

Answer 29

then s(t+h)-s(t) is the distance

Answer 30

so
st+sh-st=d
sh=d?

Answer 31

s is a function!!!

Answer 32

oh..just kidding then don't be mad >_<

Answer 33

s(t) means position of an object in instant (t) not s*t

Answer 34

wouldn't the equation be
\[\frac{ (t+h)-t }{ h }=d\]

Answer 35

nope

Answer 36

s(t+h)-s(h) is the distance

Answer 37

isn't that the difference quotient equation???

Answer 38

t+h-t is the distance?

Answer 39

do you measure distance in s?

Answer 40

the distance is the difference in positions

Answer 41

i don't know I am so confused :(

Answer 42

s(t) is a position at instant (t)

Answer 43

s(0)=-2, then at t= x he is in s(0)=-2m, s(1)=-8, then in one second delta(s)=|-8--2|=6

Answer 44

get it?

Answer 45

no im done

Answer 46

http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html

Answer 47

read the velocity section

Answer 48

s(0)=-2, then at t= 0 he is in s(0)=-2m, s(1)=-8, then in one second delta(s)=|-8--2|=6