Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 6: Q.5 (page 154)

A 65kg gymnast wedges himself between two closely spaced vertical walls by pressing his hands and feet against the walls. What is the magnitude of the friction force on each hand and foot? Assume they are all equal.

Short Answer

Expert verified

The friction force on each hand and foot has a value of 160N.

Step by step solution

01

Magnitude : 

The greatest extent of size and direction of an item is defined as magnitude.

02

Explanation : 

Mass of a gymnast = 65kg.

Gymnast's free body diagram,

For the equilibrium requirement, Newton's second law is used,

∑Fy=0

In order to resolve the components of friction forces and the gymnast's weight in the y-direction,

-mg+4Ff=0

Ff= Friction force on each hand and foot.

m= mass of the gymnast.

g= acceleration due to gravity.

Substitute 65kg for m, localid="1647704475058" 9.81m/s2for gto find Ff.

-65kg(9.81m/s2)+4Ff=0Ff=637.65kg·m/s24≈160N

Hence, the friction force on each hand and foot has a value of160N.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

A construction worker with a weight of 850N stands on a roof that is sloped at 20°. What is the magnitude of the normal force of the roof on the worker?

Seat belts and air bags save lives by reducing the forces exerted on the driver and passengers in an automobile collision. Cars are designed with a “crumple zone” in the front of the car. In the event of an impact, the passenger compartment decelerates over a distance of about 1 m as the front of the car crumples. An occupant restrained by seat belts and air bags decelerates with the car. By contrast, an unrestrained occupant keeps moving forward with no loss of speed (Newton’s first law!) until hitting the dashboard or windshield. These are unyielding surfaces, and the unfortunate occupant then decelerates over a distance of only about 5 mm.

a. A 60 kg person is in a head-on collision. The car’s speed at impact is 15 m/s. Estimate the net force on the person if he or she is wearing a seat belt and if the air bag deploys.

b. Estimate the net force that ultimately stops the person if he or she is not restrained by a seat belt or air bag.

A2.0kgobject initially at rest at the origin is subjected to the time-varying force shown in the figure. What is the object’s velocity att=4s?

Zach, whose mass is 80 kg, is in an elevator descending at 10 m/s. The elevator takes 3.0 s to brake to a stop at the first floor.

a. What is Zach’s weight before the elevator starts braking?

b. What is Zach’s weight while the elevator is braking?

FIGURE EX6.20shows the velocity graph of a 75kg passenger in an elevator. What is the passenger’s weight

a. At 1s?

b. At 5s?

c. At 9s?
See all solutions

Recommended explanations on Physics Textbooks

Scientific Method Physics

Read Explanation

Dynamics

Read Explanation

Engineering Physics

Read Explanation

Geometrical and Physical Optics

Read Explanation

Physics of Motion

Read Explanation

Medical Physics

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free