(adsbygoogle = window.adsbygoogle || []).push({}); Launching of a Potato (Involve kinetic and potential energy and an angle!!)

A potato of mass 210 g is launched from a potato gun, being released from a height of 0.6 m, at an angle of 47o with respect to the horizontal, and with an initial speed of 38 m/s. Assume the effect of air resistance can be neglected.

mass = 210 g or 0.210 kg

height (initial) = 0.6 m

θ (angle) = 47 degrees

Vo (initial velocity) = 38 m/s

a. What is the horizontal component of the potato’s velocity at the time it is launched?

b. What is the speed of the potato when it is its maximum height? Hint: the answer is not 0!

c. Calculate the kinetic energy of the potato when it is launched.

d. Calculate the gravitational potential energy of the potato when it is launched.

e. Calculate the kinetic energy of the potato when it reaches its maximum height.

f. Using the principle of energy conservation (that is, a Unit 2 technique not a Unit 1 technique), determine how high above the ground the potato rises before beginning its descent.

Vectors have always been an issue for me in this class...as soon as I see an angle I get all mixed up.

Part A: I'm not really sure what is meant by "horizontal component". The potato is being launched upward so it has an x and y value. Would its vertical component be 38 m/s in the y direction? I have no clue...

Part B: This is projectile motion...the first thing I thought of is 0! Why is it not 0? Is it because the potato is still moving horizontally, just not vertically?

Part C: Okay so K = 0.5 * m * v^2

K = 0.5 * 0.210 kg * 38 m/s ^2

K = 150 J

Now there is an angle involved...I have no clue how or if that needs to be factored in...

Part D: U = mgh

U = 0.210 kg * 9.8 m/s^2 * 0.6 m

U = 1.23 J

And again with the angle...

Part E: I think once I get the angle part dealt with I'll be able to solve the rest of this...

Part F:

I know you guys don't want to do our homework for us, which I completely understand, but I really can't do this problem correctly without knowing how to handle the angle. Once that part is pointed out, I should be able to do the rest of the problem.

Thanks 1 million times to who ever can help!! =]

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

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Launching of a Potato (Involve kinetic and potential energy and an angle )

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