# Physics average velocity problem

1. Jan 24, 2005

### oldunion

Larry leaves home at 9:0 3.00 and runs at constant speed to the lamp post. He reaches the lamppost at 9:0 9.00, immediately turns, and runs to the tree. Larry arrives at the tree at 9: 12.0 0.

from 0-1200 yds. the lightpost is at 200, house at 600 and the tree at 1200

i keep getting absurd numbers like 155.55 yd/s, they want the answer in minutes. And unless larry is a jet thats not going to happen. Ill be up all night because im lost in space :tongue:

Last edited: Jan 24, 2005
2. Jan 24, 2005

### dextercioby

If i may ask,how on Earth & Milky Way did u get yards/second,when u're given time intervals in minutes??

Daniel.

3. Jan 24, 2005

### oldunion

because when im thinking very hard i could mistake orange for black. Youre right it is in minutes. i got two realistic answers of 200yds/min and 155.55yds/min. both incorrect. i know the formula for ave velocity but still lost. 4 hours left till class, someone please

4. Jan 24, 2005

### dextercioby

U need to draw a diagram.The first number is simple...Roughly 33yd/minute.For the second u need to take into account that he turns back to the house andthen goes to the tree to p**... :tongue2:

Daniel.

5. Jan 24, 2005

### oldunion

yes, 33 plus 66 (from light to tree) this would be 99.99. wrong. well by this time ive already guess wrong about 7 times, which proves the ole creed "you never lose if you keep trying" completely defunct as my score is now laughably low. inches from giving up. mastering physics is the devil

Last edited: Jan 24, 2005
6. Jan 24, 2005

### michaelw

redraw where things are mate
the guy running (both times) apparantly increases his speed by a factor of 5 (which is really weird) in running from the lamp to the tree

7. Jan 24, 2005

### oldunion

no velocity is constant. this is the 2nd chapter of my physics book so its supposed to be easy. and i know for a fact the velocity is constant. and diagrams, i have 3 pages of scribbles. something about physics just never sat right with me.

8. Jan 24, 2005

### oldunion

the answer was 66.7, no credit.