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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.

length of string. A ten gram bullet moving with a horizontal velocity of nine hundred meters per second strikes passes through and emerges from the block which was initially at rest with the horizontal velocity of three hundred meters per second. To what maximum height above its initial position will the block hang?

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, Tom from everystepphysics.com and everystepcalculus.com. A mass on a ramp problem, test problem. Let’s do it. You have to put physics in the entry line of the calculator to get to my menu. And because the problem ask for acceleration, I always recommend you circle what’s asked for and then on the side, put down what’s given. In this case force Newtons and theta and then mass. So right now we’re gonna go to, it asks for acceleration. Press number two here. And then we’re going to scroll down to what’s given because there’s many of those in here. It’s not mass, and theta, and friction force. It’s mass, theta, and newton. There we go,letter E. You have to press Alpha before you enter anything in these entry lines. Alpha 3 kilograms. And then the force is alpha 25. And the angle given is 30. Alpha 30. I always show you what you’ve entered, you can change it if you want. I say it’s okay. Here’s the formula. Write this down on your paper right away. I like to use A equals acceleration because a lot of times and most the time in Yahoo or wherever you search, you don’t know what they’re asking for you don’t know what this letter means. Professors and people do not put that down. I like to put that down first in my problem so we all know what we’re talking about, exactly not almost. And here’s the to answer here: 25 times cosine at thirty minus 3, which is the mass times gravity, etc. divided by three, all the quantity, divided by three. Here’s the step-by-step 2.3119. You got an A on this problem. Go to my site, buy my programs everystepphysics.com. Pass your classes and subscribe if you wanna see more movies. Thank you.

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 and everystepcalculus.com. I going to do another physics problem. I’ll read it. A European sports car dealer claims that this product will accelerate at a constant rate from rest to a speed of 100 kilometers per hour in eight seconds. What is the speed after the first five seconds of acceleration? So, let’s do it. Physics to get into my menu. Open closed parentheses. That tells a calculator you want to do a program. And we’re going to go because I want you to circle things, what’s asked for in the problem and I want you to write on the right, I want to write was given so you keep clear mind of everything. In this case was speed. Speed velocity is the same. Just for your information, velocity is a vector can be negative or go in any direction. Speed is a scaler and it’s only positive, you can never have it negative. But otherwise they’re essentially the same. So we’re going to, I’m going scroll up to go to the bottom on the menu here and I’m going to scroll up to speed. Right there. And then we choose what’s given. Well and what’s given is final velocity in time. So I’m gonna go up in the menu here and see if that’s in here. And here’s velocity and time, right here. Choose that. They’ve given you initial velocity or final velocity. So you press Alpha, press Alpha first before entering anything into the entry lines. Alpha 100. And notice they give you kilometers, change the meters per second. So I do that for you. You write this on your page do the conversion. And is acceleration given? No. No acceleration is given. Okay and then Alpha. Alpha and what time was given. Eight seconds. So then I do the acceleration for you here it is right here. And then is another time given. I say yes. So I’m going to go Alpha five. And here’s the answer for the test problem. 17.4 meters per second. Pretty neat, huh? everystepphysics.com Go to my site, buy my programs and maybe subscribe for more videos. Thank you