# College Physics time and distance question

*label*Science

*timer*Asked: Sep 10th, 2014

*account_balance_wallet*$5

### Question Description

you are standing on the rim of a canyon. You drop a rock and in 7.0s hear the sound of it hitting the bottom (the speed of sound in air is about 340m/s)

Calculate how fast the rock is traveling when it hits the bottom?

## Tutor Answer

You can hear the sound of rock after 7 seconds of getting dropped

Here we have to consider the time the rock takes to hit the ground before it makes a sound by hitting

The total time = time taken by rock to hit the ground +time for the sound to return up the canyon

Total time = a+b

a.Time taken for rock to fall/hit the ground

d=1/2gt^2 {g=9.8}

** t=square root of (2d/g)**

b.Time for the sound to return up the canyon

speed of sound in air is 340m/s

*t=d/340(as Distance = Velocity* Time )*

Total time =7

So we have

Square root of (2d/9.8) +d/340=7{calculate this and you get the answer)

Solve d

Distance of canyon is

------ sec for the rock to drop

------- sec for the return sound

Let me tell you the other experts answerwhich you bested is incorrect even the multiplication is wrong just multiply 340*7 =2380*flag*Report DMCA

Brown University

1271 Tutors

California Institute of Technology

2131 Tutors

Carnegie Mellon University

982 Tutors

Columbia University

1256 Tutors

Dartmouth University

2113 Tutors

Emory University

2279 Tutors

Harvard University

599 Tutors

Massachusetts Institute of Technology

2319 Tutors

New York University

1645 Tutors

Notre Dam University

1911 Tutors

Oklahoma University

2122 Tutors

Pennsylvania State University

932 Tutors

Princeton University

1211 Tutors

Stanford University

983 Tutors

University of California

1282 Tutors

Oxford University

123 Tutors

Yale University

2325 Tutors