Skip to main content
Ch. 7 - Logarithmic, Exponential Functions, and Hyperbolic Functions
Briggs - Calculus: Early Transcendentals 3rd Edition
Briggs3rd EditionCalculus: Early TranscendentalsISBN: 9780136847243Non è quello che usi tu?Cambia libro di testo
Capitolo 7, Problema 7.3.97d

Terminal velocity Refer to Exercises 95 and 96.


d. How tall must a cliff be so that the BASE jumper (m = 75 kg and k = 0.2) reaches 95% of terminal velocity? Assume the jumper needs at least 300 m at the end of free fall to deploy the chute and land safely.

Guida verificata passo dopo passo
1
Recall the velocity function for an object falling with air resistance proportional to velocity: \(v(t) = v_{\text{terminal}} (1 - e^{-\frac{k}{m} t})\), where \(v_{\text{terminal}} = \frac{mg}{k}\).
Calculate the terminal velocity \(v_{\text{terminal}}\) using the given mass \(m = 75\) kg, gravitational acceleration \(g = 9.8\) m/s², and drag coefficient \(k = 0.2\): \(v_{\text{terminal}} = \frac{75 \times 9.8}{0.2}\).
Set the velocity to 95% of terminal velocity: \(v(t) = 0.95 \times v_{\text{terminal}}\), and solve for time \(t\) using the velocity formula: \(0.95 = 1 - e^{-\frac{k}{m} t}\).
Rearrange to isolate the exponential term: \(e^{-\frac{k}{m} t} = 1 - 0.95 = 0.05\), then take the natural logarithm to solve for \(t\): \(t = -\frac{m}{k} \ln(0.05)\).
Find the distance fallen during time \(t\) by integrating the velocity function or using the position formula: \(s(t) = v_{\text{terminal}} \left(t + \frac{m}{k} e^{-\frac{k}{m} t}\right)\). Add the 300 m needed for chute deployment to find the total cliff height.

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.
Durata del video:
10m

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

Terminal Velocity

Terminal velocity is the constant speed an object reaches when the force of gravity is balanced by the drag force from air resistance. At this point, acceleration stops, and the object falls at a steady speed. It depends on factors like mass, drag coefficient, and air density.
Video consigliato:
Percorso guidato
06:29
Derivatives Applied To Velocity

Differential Equations in Motion with Air Resistance

The motion of a falling object with air resistance is modeled by a differential equation balancing gravitational force and drag force. Solving this equation gives velocity as a function of time or distance, which is essential to determine how long or how far it takes to reach a certain fraction of terminal velocity.
Video consigliato:
07:39
Classifying Differential Equations

Free Fall Distance and Safety Constraints

In problems involving BASE jumping, the total height must account for the distance needed to reach a target velocity and the safety margin for parachute deployment. Understanding how to partition the total height into acceleration and deceleration zones ensures the jumper can safely land.
Video consigliato:
Percorso guidato
07:39
Pumping Liquids
Pratica correlata
Domanda del libro di testo

Chemotherapy In an experimental study at Dartmouth College, mice with tumors were treated with the chemotherapeutic drug Cisplatin. Before treatment, the tumors consisted entirely of clonogenic cells that divide rapidly, causing the tumors to double in size every 2.9 days. Immediately after treatment, 99% of the cells in the tumor became quiescent cells which do not divide and lose 50% of their volume every 5.7 days. For a particular mouse, assume the tumor size is 0.5 cm³ at the time of treatment.

d. Plot a graph of V(t) for 0 ≤ t ≤ 15. What happens to the size of the tumor, assuming there are no follow-up treatments with Cisplatin?

40
views
Domanda del libro di testo

Evaluating hyperbolic functions Evaluate each expression without using a calculator or state that the value does not exist. Simplify answers as much as possible.


d. sech (sinh 0)

59
views
Domanda del libro di testo

Energy consumption On the first day of the year (t=0), a city uses electricity at a rate of 2000 MW. That rate is projected to increase at a rate of 1.3% per year.


c. Find a function that gives the total energy used (in MW-yr) between t=0 and any future time t>0.

35
views
Domanda del libro di testo

Explain why or why not Determine whether the following statements are true and give an explanation or counterexample. Assume x > 0 and y > 0.


e. The area under the curve y = 1/x and the x-axis on the interval [1, e] is 1.

51
views
Domanda del libro di testo

Explain why or why not Determine whether the following statements are true and give an explanation or counterexample.


d. If the rate constant of an exponential growth function is increased, its doubling time is decreased.

53
views
Domanda del libro di testo

Explain why or why not Determine whether the following statements are true and give an explanation or counterexample. Assume x > 0 and y > 0.


c. ln (x + y) = ln x + ln y

79
views