WEBVTT
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Hello. We're here, too. Find the tension
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force of Ah horizontal cable and the force that the
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wall exerts at the pivot point on this being.
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So let's start with labeling what forces are actually on
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our being. This would be our attention force.
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This would be the downward force, too, to
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the radiator, which we is a known value off
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Warren 20 Newtons. And here is our force or
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wall exerts. Call that force of the wall and
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it's at the pivot point of our being. We
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will utilize Newton's second law using both the torque portion
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as well as or horizontal com home it portion.
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We know since this beam is not living, that
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all forces both in the X and Y direction are
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zero as well as all of our net torques.
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Remembering torque is forced times the perpendicular lever arm.
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If we use the wall, here is a pivot
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point. We know we have two forces that are
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contributing to works in opposite directions, the tension of
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the wire as well as the weight of the radiator
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. So for tension of our wire, we know
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this to be a true statement that these two it
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works are equal to each other. Now, remember
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, lever arm is calculated or found. Bye.
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Finding the perp particular distance to the torque from the
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pivot point for the tension Force this because this angle
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is 15 degrees. This would be l signed 15
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or radiator here. We know this angle. It's
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a complimentary to that. So it would be 75
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. So this would be f G l sign 75
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solving here for attention. No, both Els are
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the same value is there? The forces are acting
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at the same point on our being attention would be
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f g sign 75 signed 15 f g is for
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20 and solving that we get a value Uh 15
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. 67. Vince for our attention force now parked
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. Our next force we were asked to sell for
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was the force the wall exerts here. We're going
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to use the horizontal components and know that they are
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also in equilibrium. So we know that the force
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attention would be equal to the horizontal component of the
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wall. That would be because I'm 15 solving for
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force of the wall that would be forced tension overcoats
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on 15 and using our value we just calculated something
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in, We would calculate that the force of the
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wall is 16 22. It's now Barbie asks an
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interesting question. It asks why it is that doctors
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would recommend lifting objects with the legs bent rather than
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bending over your back in this manner. If you
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think about it. If our if we lift with
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our knees bent, what it amounts to is moving
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this bar more vertical. If it is, that
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is, in fact, true. That decreases this
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angle here, increasing this angle, and that would
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cause this ratio to become more closer to one.
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And in fact, the tension would be equal to
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the wait of the radiator. Remember the tension we
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compared to the bat, the force that the bath
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muscle would exert on our back? That would decrease
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that force? And, of course, the tension
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was decreased. So would the force that the wall
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is exerting, which is the force that the disc
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in the lower back exerts on the back. Thank
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you for learning with me