Saturday

January 31, 2015

January 31, 2015

Posted by **dave** on Sunday, November 29, 2009 at 9:52pm.

i am solving for tf and i have it worked all the way down to:

-100m(tf)-100m(tf) / -10m/s^2(tf)^2

or

-200m(tf) / -10m/s^2(tf)^2

is the answer 20 seconds? algebra is not my strong suit =(

- Need problem statement -
**Damon**, Sunday, November 29, 2009 at 9:58pmWhat is the problem here. Is it something fired at some speed at some angle?

- college physics -
**dave**, Sunday, November 29, 2009 at 10:03pmyes.. it's the "brothers of mercy" problem.

a plane is flying at 40 m/s, descending at an angle of 37 degrees to the horizontal. it is 100 m in the air and it is trying to drop a package to a man at R distance. what is R?

to find R, i needed to solve for time. that's where the quadratic came from

- college physics -
**Damon**, Sunday, November 29, 2009 at 10:55pminitial speed down = 40 sin 37

= 24.1 m/s

falls 100 meters, get speed down

v = 24.1 + 9.8 t

distance down

100 = 24.1 T + 4.9 T^2

4.9 T^2 + 24.1 T - 100 = 0

T = 2.68 s

now horizontal speed constant for 2.68 seconds

d = (40cos37)2.68

= 85.6 meters

**Answer this Question**

**Related Questions**

chemistry - Four solution are prepared and mixed together: Start with 100.0ml of...

Phoenix - Projectile motions problems are some of the most important problems ...

chemistry - calculate the change in pH when 9.00ml of 0.100M HCl(aq) is added to...

Physics - A projectile is fired from ground level with a speed of 40 m/s at an ...

physics- what did i do wrong - If the bus is 100 meters ahead of the car and the...

Physics - Which of the following statements about projectile motion is not ...

chemistry - Ka for hypochlorous acid, HClO, is 3.0*10^(-8). Calculate the pH ...

sciecne - An airplane is being floen at 1500km/h at 100m above level ground. The...

Physics - A particle experiences a constant acceleration that is north at 100m/s...

CHEM-102 - Ka for hypochlorous acid,HClO is 3.0x10^-8. Calculate the pH after 10...