Kinematics equation which is Y = vt+ 1/2gt^2

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A rock climber throws a first aid kit at 11 m/s at a 65-degree angle, and the kit reaches its highest point when caught. To solve for the height of the second climber, the initial velocity is separated into horizontal and vertical components using trigonometric functions. The vertical motion is analyzed with the kinematic equation Y = vt + 1/2gt^2, where the final vertical velocity is zero at the apex. The time to reach the apex is calculated using the equation V(final) = V(initial) + gt, resulting in a time of approximately 1.017 seconds. The discussion also touches on deriving the height equation from kinematic principles.
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Hello guys...Here again i came up with another question I guess you help me out.Here is the question.

1.A rock climber tosses a small first aid kit to another climber higher on the mountain.the kit is thrown at velocity of 11m/s at velocity of 65 degree from horizontal.when the kit is caught,it is at the apex of its path.how high up is the second climber?

Here is what i did.

I separate it into two which is

Horizontal
X = vt
V = 11m/s
V(x) = (cos 65) * 11
X(final)=


Vertical
Y = vt + 1/2gt^2
v=11
v(y)=(sin65)11
t=
y(final)=


I have all given value but how can i find the time without knowing at list Y final or

Y final without knowing the time.

i can plug in the formula but i have to have either time or y final.

thank you
 
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Haha I did this problem yesterday for an online quiz, I'll help you out a bit.

This is how I did it. The initial velociy is 11 m/s.

V_0 = 11 m/s

The following equation will give you your x-component of velocity and your y-component of velocity respectively. Which is what you said you needed.

v_0x = v_0(cos65)
v_0y = v_0(sin65)

You know the acceleration of a_y = -9.8 m/s2.

And use one of your kinematic equations to solve the problem

After you get your final velocity (use one of your kinematic equations its simple). The formula for height is (v_y)^2/(2)(a_y).

I edited the original content b/c I think I was giving too much away, plus I already have a warning for when I did my first post.

Hope this isn't TOO much help.
 
Last edited:


thanks for your help.I got the answer finally using V(final) = v(inital) + gt ...its vertical
v final = 0
so t= 1.017.
After that i use kinematics equation which is Y = vt+ 1/2gt^2.

how ever i have a question for you.


BuGzlToOnl said:
The formula for height is (v_y)^2/(2)(a_y).
.

how did you drive the Hight equation
 
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