a golfer is teeing off on a 170m long par 3 long. the ball leaves with a velocity of 40m/s at an angle of 50 degrees to the horizontal. assuming that she hits the ball on a direct path to the hole, how far from the hole will the ball land ?

Question

rane · Answer

@austinL

austinl · Answer

First things first. Physics problems are like essays.
You need to have all your supporting information for your thesis.
Meaning, you need to have everything that you know written down, draw what you have been given. And use that to form an argument as to what the answer is.

Lets start with that. What do we know, and picture :)

rane · Answer

i dont understand the q' 
I'm confused

austinl · Answer

Lets draw a picture :)

|dw:1393249453739:dw|

rane · Answer

yh?

austinl · Answer

I have to go soon, perhaps one of the other helpers here could assist?
I need to prepare for class.

rane · Answer

oh ok 
anyone???

parthkohli · Answer

Hi, may I help?

rane · Answer

sure

parthkohli · Answer

Do you know a little bit of trigonometry and projectile motion?

rane · Answer

yup, i have been doing it since past 4 weeks 
just don't get this q;

parthkohli · Answer

As I said in the chat, this question is just a complicated way of asking you the time taken for the projectile to end, if you read it carefully.

rane · Answer

no, its asking us the displacement between the point where it landed to from the hole

parthkohli · Answer

whoops -- I'm too stupid :P

do you know the formula for the range?

anonymous · Answer

@ParthKohli isnt it asking for the distance covered by ball??????

rane · Answer

exactly @rizwan_uet

parthkohli · Answer

@rizwan_uet Yeah, I read it wrong.  Way too stupid!

parthkohli · Answer

Do you, anyway, know the formula for the range of any projectile?  We can manage without it too, but always helps.

parthkohli · Answer

Actually, the displacement in the horizontal direction, but you're right.

rane · Answer

$$r= u \cos \Theta * t$$

rane · Answer

i did say displacement

anonymous · Answer

formula for finding the range of projectile is 

R = (vi^2 sin 2theta)/g

where vi = initial velocity and g= 9.8m/s

parthkohli · Answer

Yes, but you don't need to know the time either!

parthkohli · Answer

And it is$$R = u \sin\theta\cos\theta \times t$$

anonymous · Answer

now vi = 40m/s  theta = 50 degrees and g = 9.8m/s 

put all these values in the above formula to get displacement @RANE

rane · Answer

i got 160.8

parthkohli · Answer

That is correct!

rane · Answer

its not, 
the answer sheet says that 
ans = 9.38m

anonymous · Answer

what is 170m rane

parthkohli · Answer

170 m is the distance from the hole.

parthkohli · Answer

So subtract the range from the distance from the hole

anonymous · Answer

ok then what does   par 3 long mean

rane · Answer

oh yh

parthkohli · Answer

That's not relevant...

anonymous · Answer

ok fine

anonymous · Answer

range is 160.7 now subtract it from 170

parthkohli · Answer

I understood the meaning of this question *now*.

anonymous · Answer

i think we should find the range

rane · Answer

ok who should i give medal to 
u both helped me out

parthkohli · Answer

Anyone.

rane · Answer

don't know who,....
would u find if i give it @rizwan_uet since u r already have one?

parthkohli · Answer

Sure.

anonymous · Answer

did you get the answer parth