Biometric algorithms & physics help plz

L

ljlugg

New member
Joined
Mar 10, 2020
Messages
17
I need to try to understand this kind of math more before my biometric paper is due in a few months. These practice questions represent the math I will need to be familiar with to construct my final paper, which is based on reconstructing accident scenes. Any help would be greatly appreciated, especially if you can share step by step processes and formula's so that I can eventually solve similar questions with set formula's. Thank you.

A) A cup that has a mass of 0.50 kg sits on a desk. Draw a free body diagram to determine the upward force exerted by the desk.

B.) Your mother borrows your truck and subsequently gets it stuck in some mud. She calls you & your brother to come rescue her. But when you arrive you decide to secure a steel cable in your tool box to a nearby tree. You & your brother then pull sideways on the cable at its midpoint & succeed in pulling the truck out of the mud. If you and your brother applied 400 N of force (F) on the cable, then what was the resulting force applied to the truck? θ = 10 ∘ Draw afree body diagram.

C.) You need to install of a new cyclotron at your local hospital. The cyclotron needs to be lifted with a engine hoist like device. So you install a chain at the center of the top of a crate containing the cyclotron. Then, you pull sideways with a direct horizontal force F. The cyclotron & crate have a combined mass of 1800kg. So what will the tension in the chain be when it makes an angle of
15%255E%255Ccirc
with vertical? Also, what would be the force F? Draw the free body diagram.
 
A): Using F = m * a you can calculate the weight of an object by multiplying its mass by the gravitational constant (9,81 or 10 m/s^2)

B): A force is a vector. It has a value and a direction. you can dissect such vectors in its x- and y components with the sin and cosine. Exactly like you do with triangles and determining its sides: https://www.grc.nasa.gov/WWW/K-12/rocket/Images/sincos.gif

C): a combination of A and B makes up C. A free body diagram consists of the objects without all of its reacting surfaces. These surfaces are replaced with corresponding (resulting) forces.

You can try to researching static mechanics at khan academy for a more in depth explanation.
 
I'm trying ot understand this more, but its still not making total sense. If you can give me a formula for B. & C. then I can work the answer out on paper, since I am getting better with cracking formulas.
 
I think for problem B this is a tension equation, with the two ends of the wire being equal to one another, with the applied force of 400N being found in the middle where the two brothers are pulling. So I'm thinking the answer would be 400 N or 200 N. I'm leaning more towards 200N, since it would be half of the tension found in the middle. I hope I'm understanding all this right?
 
I worded that wrong, what I meant to say is since the F is 400N in the middle of the wire, wouldn't it be 400N on both ends too? But wouldn't the 10 degree angle its being pulled mean that I need to subtract 10 degrees from my final answer?
 
You must log in or register to reply here.
Top