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An open rectangular box has a square base. If the volume must be 32 cubic inches, find the dimensions of the box with minimum surface area.

Hello, Everyone. Tom from everystepphysics.com and everystepcalculus.com. We’re going to do A Modified Atwood Machine. This time with friction on the table there. And you’ll notice the ninety degree angle. And that angle goes from when the two masses are hanging and he said the pulley that would be zero angle and then up at a table will be ninety degrees so on all the angles in between, I’m always bothered with physics formula’s where they don’t have a complete formula. And it’s not clear. So anyway, the cosine is in the formula and cosine of ninety degrees is zero. So we see how that works. So that’s the only thing to remember that it has an angle and UK also. So we’re gonna get going here. Physics, go to my menu. I’m going to scroll down to Atwood Machine, here. And I’m gonna scroll up to Modified Atwood with theta and UK. I’ll show you a picture in case you didn’t know how to draw it. Now, of course this would be ninety degrees table. I have that in the modified section of this program, also. I’ll show you that. We’re going to put in a mass here. M1 is equal to 5. You have to push Alpha before you enter anything in these entry lines here. So it’s Alpha 5 kilograms and then M2 is Alpha 11 kilograms. Theta then would be ninety degrees and UK would be point 8 as it’s given. I always show you which have entered, you can change it if you want. I say it’s okay. Here’s the formula. Notice UK’s in the second part of this equation. All divided by the total masses. And then we have cosine here. They enter the variables. And here’s the answer: 6.744 meters per squared. You notice how the second term of this formula became 0 because cosine of ninety is 0. Pretty neat, huh? everystepphysics.com and everystepcalculus.com. Go to my site, buy my program, pass your classes, and subscribe if you wanna see more movies. I also give tension here. See the tension because tension uses the acceleration that we found previous. Have a good day!

Hello, Everyone. Tom from everystephysics.com. Here’s a test problem. I’m gonna read for you. A cart is given an initial velocity of 5 meters per second and experiences a constant acceleration of 2 meters per second squared. What is the magnitude of the carts displacement during the first six seconds of it’s motion? I always want you to in these problems to circle what’s asked for. In this case displacement and I want you to write on the side of the program what’s given. Which is in this case initial velocity, acceleration, and time. So, let’s the do it. You have to put physics in here with the open/close parentheses to get my menu. We’re gonna scroll down to displacement because that’s what it’s asked for. And we’re gonna choose what’s given which is velocity, acceleration, and time. There’s a formula for it. You have to press Alpha before you enter anything in these entry lines. So the the initial velocity is Alpha five and meters per second. I do the conversions. Is acceleration given? Yes. Acceleration alpha 2. And the time is alpha 6. I always show you what you’ve entered. You can change it if you want. I say it’s okay. Here’s the answer: letter C

Hello, Everyone. Tom from everystepphysics.com Here’s a test problem. I’m going to read it for you. A cart is given an initial velocity 5 meters per second and experience’s is a constant acceleration a two meters per second square. What is the magnitude of the carts displacement during the first six seconds of its motion? I always want you to in these problems to circle what’s ask for. In this case displacement and I want you to write on the side of the program what’s given. Which is in this case initial velocity acceleration in time. So let’s do it. Put physics in here with the open/close parentheses to get to my menu. We’re going to scroll down to displacement because that’s what it asks for. I’m going to choose what’s given which is velocity acceleration in time. There’s a formula for it. You have to press Alpha before we enter anything into the entry lines. So the initial velocity is Alpha five and meters per second. I do the conversions. Is acceleration given? Yes. Acceleration Alpha 2. And the time is Alpha 6. I always show you what you’ve entered. You can change it if you want. I say okay. Here’s the answer. Letter C, on the test. Pretty neat, huh? everystepphysics.com Go to my site, buy my programs and subscribe to me so you can see more movies. Thank you

Hello everyone, this is Tom from everystepphysics.com. We’re gonna do a problem that was is in a test and asked from a customer. And relating to path of objects. So, let’s get started. Physics is my key to put in this entry line here in the calculator. To get my menu, you press enter and we’re already at path of objects.

You can see pressure, pressure gauge,pulley, radius, roller coaster; all kinds of things in this menu.

for you to pass your physics test. Path of objects. I gave you three choices. Notice that there’s they ask if they’re angle or if the velocity is given or neither is given. In this case, neither was given. So we’re gonna choose number three. You can scroll down to it or you can press the number before and I like the press the number before. And a course they gave me the the height. His ball is rolling off a table and height of the table is… We have to press alpha before you enter anything in these entry lines here. The height is

Alpha 19.6 You always put that in and I always ask you or give you the choice of what they have entered sometimes you’ll enter inches or feet, or anything. It all changes to meters and in this case meters so we’re going to choose number two. And then the distance along the ground. They say this ball drop 6 meters from the edge in the table. We’re going to press alpha 6 meters. Seemingly a simple problem isn’t it, huh? Initial Heights thats i, initial height, that’s 19.6 meters and the distance is from the table is equal to 6 meters. I’ll show you what you’ve entered so you can change it if you want. I say it’s okay. And they ask you to find the time in a air. Well, that’s the time to the ground 1.999 seconds. Basically two seconds to the ground. here’s the exact equations here. You have to find that before you can find the initial speed. Remember speed is absolute, in other words, you can’t be negative. Velocity is a vector can be negative or positive and shows direction and magnitude. Speed shows magnitude but doesn’t show any direction, etc. And of course the ball rolling off the table has to be plus, can’t be minus. And so the answer is 6.8

meters per second. Pretty neat, huh? everystepphysics.com, go to my site, buy my program and pass your physics class. Very difficult classes. And also subscribe to me so you can see future videos and blog.

This is a video from every step physics dot com demonstrating how my programs work with the t i 89 titanium calculator and other calculators in the t i system for physics and calculus problems ah this is better than physics help on line because you download the programs right into you calculator and you have all the help you need ah for what I’ve programmed which is quite a bit and let’s get started on how they work you press second alpha to put p h y s i c s in the entry line of the calculator press alpha to put the open and closed parenthesis press enter and you’re into my menu

many things here for your help on line whatever you have to

choose what you want and uhm do center of mass here

ah here’s the formula center of mass is the

sums of these ecetera and I give you the choice of

two masses or two masses in the x y plane

three masses x axis three masses x y plane

four masses x y plane let’s do number four

three masses in x y plane first mass

you have to put alpha before you enter anything into the entry

lines of my programs here alpha eight first mass

we’ll say it’s kilograms I give you that choice though

alpha twelve kilograms

and here’s the third one alpha six kilograms

first coordinate x equals four

meters second coordinate

the y alpha

let’s go minus six meters

second coordinate for the x value alpha seven

meters and then the y value

alpha minus four meters third coordinate

alpha seven meters alpha six meters

I show you the whole thing that you’ve entered so you can

change it if you want if you’ve made a mistake

we’ll say it’s ok and you’re doing the sums of these

remember and here’s the calculations

write everything down on your paper just as you see it

like you’re doing the calculations yourself center of mass is six point zero eight meters

and the x y z is equal to six point zero eight zero zero

pretty neat huh every step physics dot com

go to my site buy my programs

and pass your physics

This is a video from every step physics dot com

demonstrating how my program work on the TI-89 Titanium calculator

and other calculators in the TI system for physics and calculus problems

here’s a problem that is on many tests in physics

and ah if a bullet traveling at three hunderd fifty

meters per second strikes a steel plate

at an angle of 30 degrees as shown It recochets off

with the same angle at a speed of three hundred twenty meters

per second what is the magnitude of the impulse that

the plate gives the bullet

and in my programs ah you

find first what the problem is asking in this case it’s asking impulse

and you go to my menu and you scroll down for impulse

and then you on the side of your problem

instead of looking at it or thinking about the problem at all you just

put what’s given here which is mass

twenty grams and initial velocity

which is three hundred fifty meters per second final velocity would be

three hundred twenty meters per second and then a thirty degree angle

and here’s the picture of what’s happening and this is really vector addition

so let’s get started here ah you have to press second alpha

to put these letters in here to get to my program menu

p h y s i c s and then you have to press alpha again

to put the open and closed parenthesis and press enter and you are into my menu

I’ve scrolled down to impulse here to save some time

but you start it brings you to the top of the menu

and then you have all these other choices and uhm

we get to impulse we press enter

gives you these variables here for impulse

and right now in this problem we want the mass

the initial velocity the final velocity

and the angle we choose that

we enter your variables you have to press alpha first

before we enter any variables into the entry lines of my programs

so were going to press alpha and put down

put in twenty it also might give you kilograms or grams

in this case it gives you the bullet as grams so I’m going to put that there

it shows you you take twent and divide it by a thousand

to get point zero two kilograms which is necessary for the formula

and the initial velocity your going to press alpha

and put in three fifty that’s the way the bullet is traveling

and it’s not in centimeters it’s in meters

so were going to choose number two you can press or scroll to that choice

final velocity alpha three twenty

meters again per second and then the angle is

alpha thirty I always show you what you’ve entered

so you can change it this looks good to me

it’s been changed from grams to kilograms etcetera

and this is vector addition who would have known that

if you just saw a problem in a test ah here’s the impulse vector resultant

ah the square root of the x axis and y axis

and the I of the impulse and here’s the formula

and then we add the the all the variables

you write this on paper you don’t think about it

and the I y is six point seven newtons second

and the answer is six point seven two three one

newtons second pretty neat huh

EveryStepPhysics.com go to my site

buy my programs and pass physics