Question

How far will a brick starting from rest fall freely in 5.0 s?

Answer 1

\[D=\frac{ 1 }{ 2 }at^{2}\]Where a is the free fall acceleration (9.8 meters per second squared)

Answer 2

it it 49?

Answer 3

25*4.9 is D = 122.5m

Answer 4

how did u get that above?

Answer 5

\[D=\frac{ 1 }{ 2 }\times9.8\times25 =122.5\]

Answer 6

ok i get it isaiah. so when they say how far an object its distance

Answer 7

Yeah. How far is your house from school? 10 km. Normal.

Answer 8

k and if i have a question like this...a brick is dropped from a 5m tall building.At 0.50 s how fast is the brick? how do i know what to do in an instance like this. like sometimes i dont know what i am looking for

Answer 9

You want to know how fast the brick is falling just at 0.50 s.

Answer 10

How fast=speed.

Answer 11

@CSmith035 Didn't you ask this question already???

Answer 12

yea i just wanted to see if someone can explain it just to make sure i havethe concept for this i am new the subject

Answer 13

Guess I suck at explaining...=(

Answer 14

we can use this equation \[D=\frac{ 1 }{ 2 }(v+u)t \] v is the final velocity, u is the initial velocity. Since the brick is dropped from rest the initial velocity is zero. the equation becomes \[D=\frac{ 1}{ 2 }vt\] Since we want v we can re arrange the equation for v, doing that I get \[v=\frac{ 2D }{ t }\]

Answer 15

it would be 4.9

Answer 16

Which is what I told you earlier....

Answer 17

road jester i think he already knows that you know.thanks for your help

Answer 18

So \[v=\frac{ 2\times5 }{ 0.5 }=20m/s\]

Answer 19

k i c.you major in physics a?

Answer 20

I will be majoring in physics.

Answer 21

aw k thanks alot for your help in explaining .do you tutor online? where r u from

Answer 22

u r still in high school?

Answer 23

No I don't tutor. I live in Canada. From Africa originally.

Answer 24

oh ok thanks for your help greatly appreciated

Answer 25

@ CSmith in America we might use 49 ft/s don't forget units.

Answer 26

kk thanks

Answer 27

Correction to my last statement United States of America, The rest of the American Continent switched to metric or si.

Answer 28

@munkeyman1985 I believe every physicist should work with SI units irrespective of where they're from!

Answer 29

@munkeyman1985 Gotta agree with @Isaiah.Feynman on this one

Answer 30

Everything should be si units, my life would be easier.