What is the tension in the cable

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The tension in the cable during the initial upward acceleration of the man is calculated to be 914.5 N, derived from the man's weight and acceleration. When the man is lifted at a constant velocity, the tension in the cable equals his weight, which is 822 N. In a separate discussion about forces acting on a moving object, a user seeks assistance in determining the direction of a third force needed for constant velocity, given two existing forces. The user initially misapplies the tangent function but later corrects their approach, concluding that the angle is 53.1 degrees from the west axis. The discussion emphasizes the importance of correctly applying trigonometric functions in physics problems.
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4) A rescue helicopter is lifting a man (weight- 822 N) from a capsized boat by the means of a cable and harness. (a) What is the tension in the cable when the man is given an initial upward acceleration of 1.10m/s^2? (b) What is the tension during the remainder of the rescue when he is pulled upward at constant velocity?

a) The mass of the man is 83.9kg

T = (83.9Kg)(9.80m/s^2+1.10m/s^2)

T = 914.5N

b) It is 822N because the velocity is constant.


5) Three forces act on a moving object. One force has a magnitude of 80.0N and is directed due norht. Another has a magnitude of 60.0N and is directed due west. What must be the magnitude and direction of the third force, such as the object continues to move with constant velocity.

I know how to find the magnitude, but have trouble finding the direction. Someone suggested tan(angle)= x/y. But when I do it out out i get a small number that couldn't possibly be the angle.

Thanks
 
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You did problem 4 OK.
Originally posted by physicszman

I know how to find the magnitude, but have trouble finding the direction. Someone suggested tan(angle)= x/y. But when I do it out out i get a small number that couldn't possibly be the angle.
Show what you did. (You must have made an error somewhere!)
 
Hi, thanks for your help.

I think I realized what I did wrong. You have to turn the formula around to solve for just the angle so its

angle = (80N/60N)/tan = 57.2

Do I answer the direction is 57.2 degrees North West?
 
angle = (80N/60N)/tan = 57.2

Thats how I got the previous answer. How do I calculate it the right way?

And I guess it would be from the X axis since the y-component of the force is greater.
 
Last edited:
Last question..

So what do I do with the 4/3 take the "arctan" of it?

Thanks
 
53.1 degrees from west axis. I hope this sounds right. Thanks again for all your help!
 
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