/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 8 A person pulls a toboggan for a ... [FREE SOLUTION] | 91Ó°ÊÓ

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A person pulls a toboggan for a distance of 35.0 m along the snow with a rope directed \(25.0^{\circ}\) above the snow. The tension in the rope is 94.0 N. (a) How much work is done on the toboggan by the tension force? (b) How much work is done if the same tension is directed parallel to the snow?

Short Answer

Expert verified
(a) 2980.62 J; (b) 3290 J.

Step by step solution

01

Understand the Work Formula

Work is calculated using the formula \( W = F \cdot d \cdot \cos(\theta) \), where \( W \) is work, \( F \) is the force applied, \( d \) is the distance over which the force is applied, and \( \theta \) is the angle between the force and the direction of motion.
02

Calculate Work with Angle 25°

Given \( F = 94.0 \) N, \( d = 35.0 \) m, and \( \theta = 25.0^{\circ} \), we use the formula: \[ W = 94.0 \times 35.0 \times \cos(25.0^{\circ}) \]. Compute the cosine of 25° and multiply to find the work done.
03

Perform the Calculation for Angle 25°

Calculate \( \cos(25.0^{\circ}) \), which is approximately 0.906. Substitute this value into the equation: \[ W = 94.0 \times 35.0 \times 0.906 = 2980.62 \text{ J} \].
04

Calculate Work When Force is Parallel

For part (b), the tension is directed parallel to the snow, which means \( \theta = 0^{\circ} \). The formula simplifies to \( W = F \times d \) because \( \cos(0^{\circ}) = 1 \).
05

Perform the Calculation for Parallel Force

Substitute \( F = 94.0 \) N and \( d = 35.0 \) m into the formula: \[ W = 94.0 \times 35.0 = 3290 \text{ J} \].

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Work Formula
In physics, the work formula is a crucial tool to understand how forces affect motion. Work is defined as the process of energy transfer when a force moves an object over a distance. The formula to calculate work is:
  • \( W = F \cdot d \cdot \cos(\theta) \)
Here:
  • \( W \) stands for work measured in joules \( (J) \).
  • \( F \) is the force applied to the object, in newtons \( (N) \).
  • \( d \) is the distance the object moves while a force is applied, in meters \( (m) \).
  • \( \theta \) is the angle between the force vector and the direction of motion.
This formula captures how different angles affect the amount of work done. If the force is directly aligned with the direction of movement, the angle is zero, and maximum work is done. Conversely, if the angle is 90 degrees, no work is done because the force does not contribute to the movement.
Angle in Physics
Angles in physics often determine how effective a force can be in doing work on an object. The angle \( \theta \) plays a vital role when calculating work using vectors. By considering both the force vector and the direction of motion, we can understand how much of the force effectively contributes to work.
When a force is applied at an angle \( \theta \), it needs to be resolved into two components:
  • The component parallel to the direction of motion contributes to work.
  • The component perpendicular to the direction does not contribute to any work.
Using trigonometry, we employ \( \cos(\theta) \) to find the effective part of the force doing the work. For example, in our exercise, the rope is pulled at \( 25^{\circ} \), meaning not all the force is helping pull the toboggan forward. Only \( \cos(25^{\circ}) \) of the force aids in the work.
Tension Force
Tension force refers to the pull exerted by a string, rope, cable, or any similar object, as in our exercise where the rope pulls the toboggan. It usually acts in the direction of the line attaching the objects and is an important concept in scenarios involving ropes or cables.
The magnitude of the tension force is determined by the force applied and is constant throughout the rope in ideal conditions without mass. In this physics exercise, the tension force in the rope is given as 94.0 N.
Tension is crucial in determining the amount of work done, especially when applied at an angle. The component of the tension force that aligns with the direction of movement will dictate the work done on the object. For practical purposes, understanding how tension works helps solve problems involving pulleys, string instruments, and suspension bridges.
Parallel Force
A parallel force, as the name suggests, is one that acts in a direction exactly parallel to the path of movement. In physics, understanding the role of parallel forces is crucial, as they maximize work done due to their alignment with motion.
When the force is parallel (\( \theta = 0^{\circ} \)), it implies that the full magnitude of force is applied towards moving the object. This ensures that the force entirely contributes to work, calculated as:
  • \( W = F \times d \)
This scenario leads to simple calculations since there is no need to account for directional components. In our example, it means calculating work done when the rope pulls directly parallel to the snow produces the maximum work output compared to any angled pull.
Trigonometry in Physics
Trigonometry in physics is essential for understanding and resolving forces applied at angles. It allows us to break down force vectors into components, making calculations about motion, equilibrium, and dynamics possible.
In the context of the exercise, trigonometry helps relate angles to the amount of work done by a force. To calculate how effectively a force contributes to motion, the cosine function is utilized. It provides the ratio of the force's direction leading to movement by calculating \( \cos(\theta) \).
The principles of trigonometry ensure that our calculations account for the angle's effect on the force, providing an accurate measurement of work done. It extends beyond angles, influencing various topics such as wave motion, oscillations, and electrical circuits, showcasing its wide application in the physical sciences.

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