The Official Homework Help Thread!

[Acey]

I don't know if this belongs here but it's a machine problem so I guess it does haha

 

So we're about to make a simple projectile machine that mimics a basketball free throw. Distance from player and the hoop is constant, height of player and height of hoop is constant. Variables are angle of shot and the velocity. Angle could easily be determined with a protractor. 

 

Is it possible to have something to set the firing speed of the projectile machine?

 

Edit: Thought of using springs then calculating the velocity of the body through the projectile. Can spring constants be determined from the springs themselves?

Edited March 29, 2016 by Acey

[Acey]

Can someone help me prove this trig equation?
Problem: (sec^2(x)-1)/(sin(x))=tan(x)sec(x)

ive tried going at it from both sides but neither sides seem to match up to the other. and the instructions don't say anything abt inequalities

Hi! You can just use the left side!

Try changing the ( sec^2(x) - 1 ) by a Pythagorean identity. Then the basic identities will follow.  :lol:

 

Here's what I got.

[spoiler]

 

Transforming left side

 

Change sec^2 x - 1 to tan^2 x (Pythagorean Identity)

 

Since tanx = sinx/cosx, tan^2x = sin^2x / cos^2x (Basic identity)

 

The resulting equation is now

 

(sin^2x / cos^2x)/ sinx = tan x sec x

 

One sin x will cancel:

 

sinx / cos^2x = tan x sec x

 

Since sinx/cosx = tanx, :

 

tanx / cosx = tan x sec x

 

And from basic identities, 1/cosx = secx

 

tanx secx = tanx secx !

 

 

 

 

[/spoiler]

[Acey]

omg thank you! ive been flipping the sin(x) into the numerator instead of just canceling ugh. this really helped a lot!

Oh, I see, that was close haha. I'm glad to have helped you! Goodluck in solving!  :lol:

[Acey]

You could also calculate the velocity of the projectile as it leaves the machine by calculating the maximum height of its flight, assuming free fall and no acceleration in the x-direction, calculate the initial y-component of the velocity using kinematics (v_i,y = sqrt(2gh) ), then finding the overall velocity using the measured angle and trigonometry (v_i = v_i,y/sin(theta) ).

 

As for the spring constant, you can measure a spring's constant by hanging weights off of it and measuring the displacement, then use Hooke's law to solve for the spring constant (k = mg/x)

I'm back again because I'm stuck haha.

 

This free throw program has three input arguments; initial velocity, height when ball is released, and angle of shot. Air resistance, and other factors are ignored. Assuming there is no board and the ball shoots perfectly in the center of the hoop (hoop diameter and ball diameter is ignored). Height of hoop and distance from hoop is constant. The only output argument in our program is binary, Successful or Not Successful.

 

How would the program be able to tell if its successful? Considering three different combinations of the input arguments, a small player, a medium-height player and a tall player.

 

Edit:

 

I just have thought of this one attempt to solution.

 

Since I'm given an h (height of player), angle theta, and the V (input arguments), I can compute the Vo needed for the ball to reach the distance from ball is released to the hoop using the angle theta and height of player.

 

Then in the program, is it alright if I compare V and Vo? When V is > or < Vo, then it is not successful

Edited April 1, 2016 by Acey

[Acey]

How could you incorporate MUSIC and ELECTRONICS?

I'm planning my thesis to be revolving around the conjunction of these two areas haha!

[Acey]

Bump again because I can't seem to find my error.

 

In a free throw shot, ignoring air resistance and other external forces, (Only variables are angle of shot, height of release, and velocity) what should you consider or compare to "know" if the shot is successful or not?

 

Program-wise. I'm using MATLAB.

[Acey]

welp I'm not amazing at this stuff and I'm not sure what you're asking but I'll try. Well wouldn't a successful shot be one that gets in the hoop? Like a 'swish' shot and not a bankshot? Also your controlling spin/rotation of the ball right?

Well, for my program, the diameter of the ring and the ball is disregarded. The spin of the ball, too. The board is not included, too. The program treats the ring just as a point and the same goes for the ball, too. Meaning if the point(ball) reaches the point(ring), it's considered a successful shot.  :lol:  

[Acey]

Statistics!

 

[spoiler][/spoiler]

How would you use the 10%? I'm going to use Z-test

[Acey]

xx

Edited May 23, 2016 by Acey

[Acey]

Having a hard time on statistics.

We have an exam on monday, about ANOVA tests. Could you guys recommend some good review materials for such subject?

[Acey]

ugh, i'm so sorry i just saw this now  :._.: it got lost in my notifications, i totally could have helped you, i took stats last semester.

 

36 = x + (8+x) 

 

x is the number of girls, 8 + x is the number of boys.

 

then combine the x's to get this: 36 = 8+ 2x

 

can you solve for x from here?

Oh that's alright! I think I passed today? :O

It's a series of ANOVA tests, Chi square and Correlation/Regression dam

 

Do you have any good practice materials for these kinds of hypothesis testing? Especially on z and t tests?

 

Btw

Could someone help me out here?

I need to determine the equation of the graph, given those limits/points in the graph, so I can make a fourier series

[spoiler]

 

 

 

[/spoiler]

Edited May 23, 2016 by Acey

[Acey]

yeah! i have these flow charts and stuff from my class last semester:

https://drive.google.com/file/d/0B3mQZH8HJe5XUW9PMm9fTVRQa0U/view?usp=sharing

https://drive.google.com/file/d/0B3mQZH8HJe5XeUkxOTQyeW5mS3c/view?usp=sharing

https://drive.google.com/file/d/0B3mQZH8HJe5XUkJMQWxTbjkzYXM/view?usp=sharing

 

unfortunately i don't have any practice problems to help you if that's what you were looking for  :._.:

 

oh it's okay! to solve 36 = 8 + 2x, you:

 

subtract 8 from both sides to get: 28 = 2x

 

then you divide both sides by 2 to get x = 14. 

 

so there are 14 girls, because x was the number of girls. then the number of boys is 22.

Oh, that's alright! Btw, thanks for these! Those are actually clear, WAAAAYYY more useful than what my prof use in class  :lol:  Thank you very much!

[Acey]

It's still a month for this project and I'm trying my best to gather everything I can as resources so here it is

 

We are tasked to design a Microprocessor Unit with the following minimum requirements:

• 8 bit data bus
• 16 bit address bus
• ALU
• Defined Register Set
• Control Unit
• Defined Addressing modes

Problem is, this lecture would be done a week or two prior to the deadline and waiting for it would mean wasting of 2 weeks. So I'm here, asking if anyone has some experience with this project and might give some tips or resources?

Currently I have Carpinelli and SAP 1/2/3 by Malvino.

As newbies, we're still a bit lost on how to start and reading Carpinelli and Malvino is a pain as it is very hard to understand everything by now. Any help will be greatly appreciated!  

 

Peace out!