We are standing at a distance d=15 m away from a house. The house wall is h=6 m high and the roof has an inclination angle β=30 ∘. We throw a stone with initial speed v0=20 m/s at an angle α= 35 ∘. The gravitational acceleration is g=10 m/s2. (See figure)
(a) At what horizontal distance from the house wall is the stone going to hit the roof - s in the figure-? (in meters)
b) What time does it take the stone to reach the roof? (in seconds)
height of roof: 6+ slope*(distance-15)
slope=sin30 notice distance is the horizontal distance from the wall. distance=vo*cos35*timeinair you know vo, given.
so using that height funcion,
hf=heightof roof=voSin35*time-4.9t^2
or
[6+ sun30*(distance-15)]*=
6+ sun30*(20*cos35*t -15)=20cos30*t-4.9t^2
solve for time in air, t. That is when it hits the roof.
Now, putting that into the horizontal distance equation: 20*cos35*t
check my thinking. Have fun.
thank you so much, sorry for being rather spamy so to say
i can't quite get the value of t
its wrong....
ss01 how do you solve this then
Even I wanted to know how to solve this problem.
Can any one tell me how to solve the first problem of the exam?
I got the answers of all problems except these 2.
i got it wrong followed your ways
@phy what other questions did you got? i got 1st one
i got all except this one
kyle and ss01 can you please tell me how to solve the 1st problem?
which part?
keep on differentiating and put the time value u vl get it
@kyle could you plz tell me how to do 2 & 3
@ss01 if you check homework 2 the 2nd last question it shows you how to do question 2.
for quetion 3 Ac must be 10m/s
so you get 10=v^2/r and from there you can solve since i don't know what value of r you got
@ kyle what is the option for 3 question
my radius is 7m and mass is 5kg
plz tell me how to do 5 & 6
@kyle what is for south pole
qustion 3
v=8.366
south pole is 0
ac=v^2/r
@anonymous plz specify
v=sqrt(r*g)
kyle ...got the 2
@anonymous what is the 3rd option for question 3
@Anonymous how do you solve for the 7th question
@kyle did you all the options for 6th one?
i got 1st 2 correct rest all wrong
I didn't get you, can you explain it properly how to do the 1st problem
for acceleration double differentiate the equation. you get only x and y vector left with some constant but no z vector
i didn't got the speed
Well, I don't know how to differentiate, can you explain it to me.
you could search on youtube there are lot of good videos on it. there are various rules too be followed.
Can you tell me how to calculate distance of the particle to the origin at time, speed of the particle and the smaller angle? I got the acceleration. Thanks
distance is the magnitude of the position vectors
speed is the magnitude of the velocity vector and
for the angle its the z vector for velocity divided by the magnitude of the velocity
Thanks. Did you get Stone On Roof Find Distance problem?
@kyle did you got angle 0?
337.64 for dis?