Mechanical Work: Force and Distance

Choose a study mode

Play Quiz

Study Flashcards

Spaced Repetition

Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Download our mobile app to listen on the go

Get App

Questions and Answers

In science, what two components are necessary for work to be done on an object?

Force and motion (correct)
Energy and mass
Inertia and momentum
Power and time

Holding a barbell stationary overhead constitutes doing work on the barbell.

False (B)

What condition must be met for a force to perform work on an object?

The force must cause the object to move in the direction of the force.

Work is calculated by multiplying the force applied to an object by the _______ the object moves.

distance Signup and view all the answers

A person pushes against a stationary wall with considerable force. According to the scientific definition of work, how much work is the person doing?

No work is done. (D) Signup and view all the answers

Any application of force on an object always results in work being done.

False (B) Signup and view all the answers

Describe a scenario where a force is applied to an object, but no work is done.

Pushing on a stationary object which does not move. Signup and view all the answers

In scientific terms, if there is no _______, no work is done, regardless of the amount of force applied.

movement Signup and view all the answers

A crane lifts a heavy load vertically. In which direction must the force act for work to be done on the load?

In the same direction as the object moves. (A) Signup and view all the answers

Match the scenario with whether work is being done in the scientific sense:

A student carrying a backpack while walking horizontally = No work is being done A weightlifter lifting a barbell overhead = Work is being done A car traveling at a constant speed on a level road (assume forces like friction and air resistance are negligible) = No work is being done A person pushing a stalled car that does not move = No work is being done Signup and view all the answers

Flashcards

What is work?

In science, work is the product of force and distance.

When is work done?

Work is done when a force acts on an object in the direction the object moves.

What does work require?

Motion and an applied force are required for work to occur.

Force and Direction

To do work, some of the force must act in the same direction as the object moves.

Signup and view all the flashcards

Calculating work

Work is calculated by multiplying the constant force acting in the direction of motion by the distance that the object moves.

Signup and view all the flashcards

Study Notes

Mechanical Work

Work means something different in science compared to its everyday meaning.
An object moves when an unbalanced force acts on it.
Work equals force times distance.
Work occurs when a force acts on an object in the direction it moves.
Work needs both motion and an applied force.
A weightlifter holding a barbell overhead does no work on it, because the barbell doesn't move.
For a force to do work on an object, some of the force must act in the same direction as the object moves.
If there is no movement, there is no work.

Calculating Work

A weightlifter lifting a barbell overhead does work.
The work is calculated by multiplying the constant force acting in the direction of motion by the distance that the object moves.
Work = Force × Distance
W = F × d