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This guide illustrates the process of solving force problems for objects on inclined planes using vector diagrams. It covers essential concepts such as normal force, friction force, and acceleration through step-by-step examples. Using an object sliding down a ramp as a reference, we explore how to set up and solve equations for force components. Detailed walkthroughs for various problems enhance comprehension, providing a foundational understanding crucial for tackling future physics challenges. Visual aids ensure clarity while engaging with complex concepts.
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World of Physics Force-vector diagram Type # 5
+y FN +x Ff Fg cos Fg sin Fg FVD diagram type 5 is an object sliding down an “inclined plane”. Because of the angle of the ramp, we tip our axis: The above diagram needs to drawn for every problem. Note that the force of gravity or “weight” is always drawn STRAIGHT down, and that the components are dotted with arrowheads and drawn parallel and perpendicular to the incline. THIS IS VERY IMPORTANT! Does your picture look EXACTLY like mine?
Problem # 1 - Question • A box massing 5.0 kg is on a plane inclined at 55° with a 0.20 coefficient of friction. • What is the normal force applied by the inclined plane? • What is box’s acceleration? A photograph of an object on an incline plane
+y FN +x Set up the two equations for each problem. Ff = .2FN 49cos55 49sin55 Fg = (5) (9.8) = 49 N Problem # 1 - Procedure Fy = FN - Fg cos(55) = 0 Fx = -Ff + Fg sin(55) = ma
Problem # 1 - Workout Fy = FN - Fgcos(55) = ma FN - (5)(9.8)cos(55) = 0 FN = 28.1 N Ff = ()(FN) = (.2)(28.1) = 5.62 N Fx = -Ff + Fgsin(55) = ma (-5.62) + (5)(9.8)sin(55) = 5a a = 6.9 m/s2 Solution: a = 6.9 m/s2
Problem # 2 - Question • A 2009-N skier is on a inclined plane of 55° with a 0.70 coefficient of friction. • What is the normal force applied by the inclined plane? • What is the acceleration? An image of a skier on a inclined surface.
+y FN +x Again: Set up the above two equations for each problem. Ff = FN Fg cos Fg sin Fg = 2009 N Problem # 2 - Procedure Fy = FN - Fg cos(55) = 0 Fx = -Ff + Fg sin(55) = ma
Problem # 2 - Workout Fy = FN - Fgcos(55) = ma FN - (2009)cos(55) = 0 FN = 1152.32 N Ff = ()(FN) = (.7)(1152.315) = 806.62 N Fx = Ff + Fgsin(55) = ma (-806.62) + (2009)sin(55) = 205a a = 4.09 m/s2 Solution: a = 4.1 m/s2
Step-by-Step guide to solve Force Problems, Type # 5 Step 1: Draw the diagram first; label & plug in the knowns. Step 2: Write the equations, first for the y and then for the x. Step 3: Plug in the numbers and solve, first for FN, then for Ff, and finally for the acceleration.
Just For Fun... What do you think about this seen? (Hint: Think in physics (force, acceleration))
The End Presented By an anonymous physics student World is Full of Physics