hey guys, my classmate and i have to design a device that will launch a golf ball 15m, using either a spring (which is what we're going to use) or elastic(adsbygoogle = window.adsbygoogle || []).push({});

we need to find the value of the spring constant(we can do that), an expression to determine the initial velocity of the ball, an equation to determine the angle required to hit the target 15m away (using the initial velocity), and lastly, an equation where we can sub in how far back we have to pull the spring and the angle we have to aim the device to launch the ball to any random displacement (the teacher will tell us on the day of)

1. The problem statement, all variables and given/known data

dx = horizontal displacement

dy = vertical displacement

ay = vertical acceleration (aka. gravity)

t = time/change in time

mass of ball = 45.7g

dx = 15.0m

dy = 0.00m (since the device will be put on the ground, the ball will be launched and will land back on the ground, therefore the vertical displacement will be 0m)

ay = -9.81m/s^2

2. Relevant equations

dx = vx(initial)*t, vx(initial) = 15.0m/t

dy = vy(initial)*t + 0.5(ay)(t^2), 0.00m = vy(initial)*t + 0.5(-9.81m/s^2)(t^2)

vy(initial) = 4.905m/s^2(t)

tan(angle) = opposite/adjacent = vy(final)/vx(final)

vx(final) = vx(initial)

vy(final) = vy(initial) + a*t = vy(initial) + (-9.81m/s^2)*t

3. The attempt at a solution

this is where we're stuck... we're not sure how to find the time it takes for the ball to travel a distance of 15.0m, therefore we don't know how to find the initial velocity, nor do we know how to figure out the angle

sorry for the confusing equations and such

thanks for the help! :)

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# Homework Help: How can i launch a golf ball 15 m?

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