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What are the general steps to solve for velocity with resistive forces?

  1. Apply Newton's Second Law ((F_{net} = ma)). 2. Set up the differential equation for velocity. 3. Use separation of variables. 4. Integrate to find the velocity function. 5. Apply initial conditions to solve for constants.

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What are the general steps to solve for velocity with resistive forces?
1. Apply Newton's Second Law ((F_{net} = ma)). 2. Set up the differential equation for velocity. 3. Use separation of variables. 4. Integrate to find the velocity function. 5. Apply initial conditions to solve for constants.
How do you find terminal velocity mathematically?
1. Set the net force equal to zero (resistive force + gravitational force = 0). 2. Solve for velocity ((v_t)), which represents terminal velocity.
What happens to velocity, acceleration, and net force as time approaches infinity when an object experiences air resistance?
1. Velocity approaches terminal velocity (constant value). 2. Acceleration approaches zero. 3. Net force approaches zero.
What are the steps to determine how quickly an object reaches terminal velocity?
1. Calculate the time constant, \(\tau = \frac{m}{k}\). 2. A larger mass or smaller k (weaker resistive force) means a longer time to reach terminal speed.
How do you analyze motion with varying resistive forces?
1. Draw a free-body diagram to identify all the forces acting on the object. 2. Write out the differential equation and then solve it step-by-step.
What is the difference between motion with and without resistive forces?
Without resistive forces: motion continues indefinitely (Newton's First Law) or accelerates constantly. With resistive forces: motion slows down, reaches terminal velocity, and acceleration approaches zero.
Compare the terminal velocity of a skydiver in a spread-eagle position versus a streamlined dive.
Spread-eagle: Lower terminal velocity due to greater surface area and air resistance. Streamlined dive: Higher terminal velocity due to less surface area and air resistance.
What is the difference between heavier and lighter objects in terms of terminal velocity?
Heavier objects: Greater terminal velocities because they have a larger gravitational force to balance against air resistance. Lighter objects: Lower terminal velocities because they have a smaller gravitational force.
Differentiate between initial velocity and terminal velocity.
Initial velocity: The velocity of an object at the start of its motion. Terminal velocity: The maximum speed achieved when forces balance.
Compare the effect of a larger mass vs. a smaller k on the time to reach terminal speed.
Larger mass: Longer time to reach terminal speed. Smaller k: Weaker resistive force, longer time to reach terminal speed.
What are the general steps to solve for velocity when a resistive force is present?
1. Apply Newton's Second Law ($\vec{F}_{net} = m\vec{a}$) to obtain a differential equation for velocity. 2. Use separation of variables to solve the differential equation by integrating with appropriate limits. 3. Use initial conditions to find the constants of integration. 4. Solve for the velocity as a function of time.
How do you determine terminal velocity mathematically?
1. Set the derivative of velocity with respect to time equal to zero: $$frac{dv}{dt} = 0$$. 2. Solve the resulting equation for velocity. This value is the terminal velocity.
What is the process to analyze motion with resistive forces using differential equations?
1. Identify all forces acting on the object, including resistive forces. 2. Apply Newton's Second Law to set up the differential equation. 3. Solve the differential equation using separation of variables and initial conditions. 4. Analyze the resulting velocity, position, and acceleration functions, paying attention to asymptotes and the time constant.
What are the steps to determine the time constant?
1. Identify the mass \(m\) of the object. 2. Identify the constant \(k\) in the resistive force equation (\(F_r = -kv\)). 3. Calculate the time constant using the formula: \(\tau = \frac{m}{k}\).
What are the steps to solve free fall problems with air resistance?
1. Draw a free-body diagram showing gravitational force and air resistance. 2. Apply Newton's second law: \(mg - kv = ma\). 3. Determine the terminal velocity by setting \(a = 0\), so \(v_t = mg/k\). 4. If required, solve the differential equation for \(v(t)\).