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Hello, everyone. This is Tom from everystepphysics.com and everystepcalculus.com. Today, we’re going to do everystepphysics.com stuff. A 1100 kilogram car is held in, oh they have plane here but it’s place. A 1100 kilogram car is held in place by a light cable on a very smooth frictionless ramp as shown in the figure. The cable makes an angle of 31 degrees above the surface of the ramp and the ramp itself rises 25 degrees above the horizontal. Note that the magnitude of gravitational acceleration of the earth is 9.8 meters per second squared. Draw a free body diagram for the car and find the tension in the cable. So how do we do this problem? Well, you go to physics to get to my menu. Then you choose tension because that’s what it’s asked for in the problem. So we go up tension, press Enter. And we have all these choices. We’re given to angles and one mass. In this case, we would choose number three. We put in there the mass of the car.Alpha 1130 kilograms.

Again, the anglesAlpha 31 degrees plus 25 degrees.We got 56.Notice if the ramp angle was given, you’d be pulling just along the frictionless ground. And so that there’s only one angle given, that would be mg times sin of theta. Which is a standard tension formula. Now if you add the car going with it going up a ramp with a angle, then and the rope is pulling on car at an angle, you have to add those angles together which is 56. Now you do the calculations. Equals 9190.1 newtons. Okay. Sometimes you have to kind of..one great thing about my programs is it gives you the formula for tension. A lot of times, a really simple simple formula, you can’t even recall them because you really don’t don’t have any way of placing them together and using them. My programs give you at least the formula for tension.

Hello everyone. This is Tom from everystepphysics.com. I’m going to do a problem that’s come up in any number of tests. It states in elastic string is stretched horizontally between two fixed points 0.08m apart. An object of weight 4 Newtons is suspended from the midpoint of the string causing the midpoint to drop a distance of .12 meters. Calculate a, the angle of each party of the string to the vertical and b, the tension in each part in the string. Let’s get started. You put physics in here with closed parentheses open/close parentheses to get my menu. Which I’ve already done. That’s in the instructions of my programs. And we’re going to I’m gonna go to the bottom of the alphabet here scroll up to the T section which is Tension. They ask for Tension and I’m going to go to Tension here. And, we’re going to scroll down to what’s asked for. There’s many many problems for tension but we’re going to scroll down because what what they gave us was weight in Newton’s. Here we have weight and the angle and here we have year we have Newton’s in the distance apart and distance drop. Number B. So we’re going to choose that one. You have to press alpha before before we enter anything in the entry lines here. Alpha and Newton’s weight was 4. The distance apart was .8. Press alpha first, meters. I always give you choices centimeters to meters, they trick you on that. Choose meters; that’s what they gave you. And alpha .12 meters again. I always show you which you’ve entered so you can change it if you want. I say it’s okay. And a lot of times I show you the picture like this. Notice we divided the total distance by 4. There’s one on each side. These are generally in physics, these are trigonometry problems. Geometry problems. So here we have the .12 and here we have the .4, .4. Those equal .8. And we have the theta for the horizontal here. And theta for the vertical here. In case they ask you for something different. And here’s the 4 Newton’s of weight right here. And we press enter and you notice that the vertical is 73.3 which is what they asked for. You write that on your paper. This formula here. In case they ask you for the horizontal. Which generally they do but not in this problem. It’s 16.7 degrees. And the tension is 1/2 4 because 4 is divided by each string. 1/2 of this is 2 of course. And then the cosign of 73.3 is 6.9602. If they ask for the vertical angle you you’d enter this formula. And/or if they ask you for the other one, you could enter this formula. They both come up with the same answer, 6.9602. Pretty neat, huh? everystepphysics.com Go to my site, buy my programs pass your physics classes. And also subscribe to new upcoming videos and blogs.

hello this is Tom

for EveryStepPhysics.com I write those programs for the TI-89

titanium and other calculators in the TI system

we’re doing this problem here which is a standard problem of

tension and um

let’s get started. Of course we put physics in here with close parentheses

open/close parenthesis so that you get to my

menu press Enter and we

we can scroll down here with the cursor or we can go

up because tension is closer to the the z, I’m going to go to the bottom of the

menu and I’m going to hold the cursor down here

go up to tension there’s tension generally in any problem whatever they ask that’s

what you go to in

my menu if they ask for acceleration you go there if they ask for velocity you go there

if they ask for…um stretch

or whatever they might ask you go that problem in this case we’re

talking about tension and of course they give you in this problem a mass and they

give you

angles two angles

and they give you the distance apart so we’re going to choose number seven

and we have to press alpha before we press anything we go

alpha 800 is the mass

in kilograms

I give you these in case whatever they

give you you have a choice and the angle is

L first angle is alpha 18, and the other angle is

alpha 10

and ask if they gave you the distance apart

the distance apart generally doesn’t have anything to do with the tension because

the angles determine the tension

and the distance apart a lot of times they throw you off with that

in this problem they ask you for extra credit to get the stretch of the

strings so I would use the distance in this case but so we say

yes distance is given then I gotta go alpha

18, you notice that they try to trick you again physics they love to trick you

they gave you 18 distance the same thing as the first

angle so you know

they could give you twenty-two or something for the distance and

make it completely different so you would not be confused but

they love that in physics

and of course you got meters so you gotta go number two in

meters I show you what you’ve entered here’s 800 kilograms 18,

18 angle 10 angle and 18 distance apart

I say it’s okay

So we’re going to move on I show you a picture of it here’s the 18 angle the 10 angle

tension one tension 2 and tension 3 is the cable that holds the

mass and so we have to solve this with 2

equations I show you the first equation here

and

we substitute that into the into the other equation

write all this down on your paper don’t put a substitute equation in there were

but.. but just put the

equations on your paper and so the

tension of t2 which would be on that side on of the

picture is 15898 newtons

and the t1

tension is 16,463 Newton’s

notice the uh, the credit that you get on this problem

in other words there’s just 10 points for doing this one here

which is just the tension on the corners mass times acceleration

and thats 7848

you got 10 points for this the other ones are five points apiece five points and

there’s a

so we found the tensions in each

system there and then I go to the

stretching of the string notice we have a,

b, c which is this part of the triangle

and d and e we have 10

degrees here notice the this angle here would be complimentary which is eighty

this is 18 so this is 72 sometimes they give you these angles too

ah, but anyways we need to find the stretch so we need to find the distance of

this which is the hypotenuse and this which is the hypotenuse of the

10 angle and so

tangent of, of times b would equal

the c a+b is equal to 18 that’s the total distance apart

and so b would be 18 minus a

and just write this stuff down you can take your time and look at it if you really wanna learn it

but I was always interested in passing tests

not completely learning physics and so the

a above that a 6.33 units I use units because I don’t know if I gave you centimeters or

whatever inches or whatever they might trick you with but anyways that portion of

the triangle a is 6.33 and then we

subtract that from the 18 we get 11.7 units and then the hypotenuse

of d

which is 6.66 units and then the hypotenuse

of a 10 degree angle is 11.8 units

we add those together 18.5 minus

what we started with so the stretch is .506 units

Pretty neat huh? EveryStepPhysics.com go to my site buy my programs and pass

your physics class and also

you might want to subscribe to to me so that you get future

programs or blogs on subjects

This is a video on acceleration in physics

and ah given regarding maybe tension when you

something is pushing or pulling with some tension

let’s get started you press second alpha

to put the letters p h y s i c s in here and press alpha again to put the

open and closed parenthesis press enter and you are into my menu

we’re doing acceleration here you can see the number of choices you have

and we can go for all kinds of work all kinds of things in my menus

regarding physics and press two to get into acceleration

press one to get into the next menu for acceleration

and we have the choice of generally in a test your given or asked

to find acceleration and therefore you go to acceleration

in my programs and you scroll down to something with tension

here you have tension with ah coefficient of kenetic friction

so we’re going to do that one ah they give you mass

you have to press alpha before you enter anything into my program entry lines here

press alpha put in eight give you the choice of kilograms or grams

tension let’s say alpha fourty two newtons the angle is alplha maybe thirteen point five

degrees and the coefficient of kenetic friction might

be point one seven five

I always show you what you’ve entered so you can change it make sure you got it right

from what’s given I say it’s ok

here’s the formula you write this down on your paper

physics is scored on partial credit and class curve

so whatever you write down you get credit for

but you’re going to get one hundred percent on this problem

the unknowns are put in for that formula you’re doing the calculations just like you

would on paper

write everything down just like you see it and i give it to you in fraction format

and also in five rounded decimal points to meters per second squared

pretty neat huh every step physics dot com

go to my site buy my programs

and pass physics

This is a video from every step physics dot com

solving a physics problem step by step and also demonstrating how my downloadable

programs work in your TI 89 Titanium calculator and other TI calculators

for calculus and physics problems andlet’s get started

to access my physics menu in my programs you goona have to press second alpha

and put the letters p h y s i c s in here and then press alpha and put

the open and closed parenthesis press enter and you’re into my menu

you can see how many things there are many many things here

you I have that outlined in my outline that you can receive

but uhm we’re going demonstrate tension right now

so I’m gonna go up here get to the t’s

It’s all alphebetical and click on that

and you have all these choices here what they give you

what happens in a physics test is they give find acceleration

or find tension or find work or something like that

so you go to my menu whatever word that is what they are finding

and then I put down as many variables as I have seen on a

on choices so right now were gonna

let’s do mass, displacement and angle and I can push the number four

or scroll to it with the cursor I’m going to push number four

and you have to press alpha before you put anything in these entry lines here

so press alpha eight put in eight

I give you the choice of grams or kilograms lot of times that happens

and we’re going to go alpha maybe four

and alpha maybe twelve point five degrees I always show you what you’ve entered

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

I say it’s ok I also tell you some hints about the problem

and maybe sometimes show you a diagram but here’s the two angles and what they are

talking about in this situation and how much tension is on this line here

and so here’s the formula and here’s the way the calculations work out

you write all of this out on your paper you get a

since physics tests are scored on partial credit

class curves you’ve just got a hundred percent on a problem

and way over the other people in the class a pretty neat huh?

every step physics dot com go to my site

buy my programs and pass physics

This is a video from every step physics dot com showing how my programs work on the TI 89 titanium calculator and other calculators and the TI system for physics and calculus problems. Okay, here’s another physics problem in many tests, very easy one but they’re not easy when you’re doing a test you don’t know what formulas to pull or what to do. This certainly is a system for that for getting these problems correct. 276 kilogram glider is being pulled by a 1950 kilogram airplane along a horizontal runway with an acceleration 2.20 meters per second squared to the right. Find the magnitude of the tension in the cable connecting the airplane and glider you’re pulling along horizontal plane. Therefore, gravity does not have any effect on it it’s not in the calculation if you’re pulling await up vertically then gravity does stake place in the calculation so this one gives you massive the glider in 1950 kilogram airplane doesn’t have anything to do with it because the weight is all on me and by the glider. So let’s see how my programs work on this one. So let’s get started in my programs yet the per second for the letters pH Yasi sees in here and personnel for but the opening close parentheses and press Enter in your into my menu. The problem is too find tension so there for you me the going why menu grow up or down to for medical to Kenshin tension and give you the mass acceleration so we’re gonna choose that one from this menu. Mary enter the mass you have to press l4b for you into anything and my aunt realizing these entry lines here of to 76 kilograms you could put grams in case the prime gave you something like that but I always do that give you the option for for that this is kilograms health 2.2 meters per second squared we show you which is better you can change it if you made a mistake they say it’s okay anna says horizontal and so shoes there as the airplanes point fighter-bombers way the cable and here’s a calculation simple calculation these in a senate tested you very quickly very accurately and be done with it mass times acceleration 6 7.2 news 30 every step physics that can go to my site by my programs and pass physics.