Skip to main content
Ch 11: Impulse and Momentum
Knight Calc - Physics for Scientists and Engineers 5th Edition
Knight Calc5th EditionPhysics for Scientists and EngineersISBN: 9780137344796Non è quello che usi tu?Cambia libro di testo
Capitolo 11, Problema 11b

A force in the +x-direction increases linearly from 0 N to 9000 N in 5.0 s, then suddenly ends. What impulse does this force provide?

Guida verificata passo dopo passo
1
Step 1: Recall the definition of impulse. Impulse is the product of force and the time interval during which the force acts. Mathematically, impulse is given by \( J = \int F(t) \, dt \), where \( F(t) \) is the force as a function of time.
Step 2: Recognize that the force increases linearly from 0 N to 9000 N over 5.0 s. A linear force can be expressed as \( F(t) = kt \), where \( k \) is the slope of the force-time graph. Determine \( k \) using the formula \( k = \frac{F_{\text{max}}}{t_{\text{max}}} \), where \( F_{\text{max}} = 9000 \, \text{N} \) and \( t_{\text{max}} = 5.0 \, \text{s} \).
Step 3: Substitute \( F(t) = kt \) into the impulse formula \( J = \int F(t) \, dt \). The integral becomes \( J = \int_{0}^{5.0} kt \, dt \). Evaluate the integral by substituting \( k \) and solving \( \int_{0}^{5.0} kt \, dt = k \int_{0}^{5.0} t \, dt \).
Step 4: Compute the integral \( \int_{0}^{5.0} t \, dt \), which is \( \frac{1}{2} t^2 \) evaluated from \( t = 0 \) to \( t = 5.0 \). Substitute the limits of integration to find the result of the integral.
Step 5: Multiply the result of the integral by \( k \) to find the total impulse \( J \). The impulse is the area under the force-time graph, which corresponds to the triangular region formed by the linear increase of force.

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:
2m

Concetti chiave

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

Impulse

Impulse is defined as the change in momentum of an object when a force is applied over a period of time. It is mathematically represented as the product of the average force and the time duration during which the force acts. In this scenario, the impulse can be calculated by integrating the force over the time interval, which gives the total effect of the force on the object's momentum.
Video consigliato:
Percorso guidato
06:00
Impulse & Impulse-Momentum Theorem

Force-Time Graph

A force-time graph visually represents how a force varies with time. In this case, the force increases linearly from 0 N to 9000 N over 5 seconds, forming a triangular shape on the graph. The area under the force-time graph corresponds to the impulse delivered to the object, which can be calculated using the formula for the area of a triangle: 1/2 * base * height.
Video consigliato:
Percorso guidato
05:59
Velocity-Time Graphs & Acceleration

Linear Increase

A linear increase refers to a steady, uniform change in a quantity over time, represented by a straight line on a graph. In this problem, the force increases linearly, meaning it rises at a constant rate from 0 N to 9000 N over 5 seconds. This characteristic simplifies the calculation of impulse, as the average force can be easily determined by taking the midpoint of the initial and final values.
Video consigliato:
Percorso guidato
07:31
Linear Thermal Expansion
Pratica correlata
Domanda del libro di testo

A 2.0 kg object is moving to the right with a speed of when it experiences the force shown in FIGURE EX11.9. What are the object's speed and direction after the force ends?

2252
views
Domanda del libro di testo

A 10-m-long glider with a mass of 680 kg (including the passengers) is gliding horizontally through the air at 30 m/s when a 60 kg skydiver drops out by releasing his grip on the glider. What is the glider's velocity just after the skydiver lets go?

1910
views
Domanda del libro di testo

A 10,000 kg railroad car is rolling at 2.0 m/s when a 4000 kg load of gravel is suddenly dropped in. What is the car’s speed just after the gravel is loaded?

1356
views
Domanda del libro di testo

Far in space, where gravity is negligible, a 425 kg rocket traveling at 75 m/s in the +x-direction fires its engines. FIGURE EX11.10 shows the thrust force as a function of time. The mass lost by the rocket during these 30 s is negligible. At what time does the rocket reach its maximum speed? What is the maximum speed?

1992
views
Domanda del libro di testo

A 600 g air-track glider collides with a spring at one end of the track. FIGURE EX11.13 shows the glider's velocity and the force exerted on the glider by the spring. How long is the glider in contact with the spring?

1855
views
Domanda del libro di testo

A 2.0 kg object is moving to the right with a speed of 1.0 m/s when it experiences the force shown in FIGURE EX11.8. What are the object's speed and direction after the force ends?

2227
views