All Flashcards
What are the steps to drawing an effective FBD?
- Identify the object. 2. List all forces. 3. Draw the object. 4. Draw force vectors. 5. Label vectors. 6. Add annotations. 7. Check for accuracy.
How do you relate FBDs to problem-solving?
- Always start with an FBD. 2. Relate FBDs to Newton's Laws (ΣF = ma). 3. Be consistent with directions.
How to derive the terminal velocity of an object sinking in a fluid using FBDs?
- Draw FBD showing Weight, Buoyant Force, and Resistive Force. 2. Apply ΣF = 0 at terminal velocity. 3. Express Buoyant Force in terms of fluid density and object volume. 4. Solve for terminal velocity (vt).
What is the process to analyze forces and motion using FBDs?
- Draw a clear and accurate FBD. 2. Apply Newton's Second Law (ΣF = ma). 3. Choose a positive direction and stick with it. 4. Solve for unknowns.
What is the first step to solving a fluid problem?
Always start with a clear and accurate Free-Body Diagram (FBD).
What are the differences between Normal Force and Buoyant Force?
Normal Force: Contact force exerted by a surface. | Buoyant Force: Upward force due to fluid displacement.
Compare the net force on an object floating versus an object sinking at terminal velocity.
Floating: Net force is zero (equilibrium). | Sinking at terminal velocity: Net force is also zero (constant velocity).
How does the buoyant force change when comparing a floating object to a sinking object?
Floating: Buoyant force equals the weight of the object. | Sinking: Buoyant force is less than the weight of the object.
Compare the forces acting on an object floating in water versus an object submerged and held in place.
Floating: Weight and Buoyant Force. | Submerged and held: Weight, Buoyant Force, and applied force.
Compare the effect of increasing the size of a sphere on terminal velocity, considering two scenarios: one where the sphere is made of the same material and one where the density remains the same.
Same Material: Terminal velocity increases due to increased weight. | Same Density: Terminal velocity increases, but to a lesser extent due to proportional increase in buoyant force.
What happens when the buoyant force equals the weight of an object?
The object floats or is in equilibrium within the fluid.
What happens when the weight of an object is greater than the buoyant force?
The object sinks.
What happens when an object reaches terminal velocity?
The net force on the object is zero, and its velocity becomes constant.
What is the effect of increasing an object's velocity in a fluid?
The resistive force (drag force) increases.
What is the effect of a non-zero net force on an object according to Newton's Second Law?
The object accelerates in the direction of the net force (ΣF = ma).