A rock of mass 40 kg accidentally breaks loose from the edge of a cliff and falls straight down. The magnitude of the air resistance that opposes its downward motion is 271 N. What is the magnitude of the acceleration of the rock?

Question

anonymous · Answer

I don't like the numbers that this gives me.. but.....

F_y = m_rock * g - F_air = m a

Solve for a.

(40 * 9.8 - 271)/40  = a

This give me an acceleration of 3.025 m/s^2....
Personally, I don't think that a rock could ever fall that slowly.. Unless it has a parachute. Anyone wants to correct me, feel free.. But this is what I got.

anonymous · Answer

it was right ^___^ thank you so much

anonymous · Answer

long reply? lol

anonymous · Answer

I'm a quiet guy.. also eating dinner.. :P

anonymous · Answer

lol ohhh, okay, well im the opposite of that ^___^ Dinner so late?

anonymous · Answer

yeah.. got home from school at 8.. long day.

anonymous · Answer

8? what the? why so late?

anonymous · Answer

my last class was over at 7:45..

anonymous · Answer

where are you from ?

anonymous · Answer

Maryland.

anonymous · Answer

why is it getting out so late?

anonymous · Answer

Well.. didn't want to go to classes at 8am. My first class starts at 11am..

anonymous · Answer

oh oh oh, you're in college?

anonymous · Answer

yeah.. I'm guessing you're in high school

anonymous · Answer

yupp, im a junior.

anonymous · Answer

Nice.. When I was in high school, I took physics as a soph.
I'm guessing that you're also just trying to get past it.. right?

anonymous · Answer

Almost passed the class too  :P

anonymous · Answer

correct (: well i have a B in here...don't know how

amistre64 · Answer

that reminds me about a clip i seen on the news last night; tourist was filming and the entire side of a cliff simply fell off into the sea right next to them.  i dont care how many handrails they got, i dont think id feel too safe after seeing that up close