Register to reply

Difference between newtons 1st,2nd,and 3rd law? How to know when to use them on a tes

by slobodan48
Tags: grade 11 physics, newtons laws, test, tomorrow
Share this thread:
slobodan48
#1
Dec10-09, 05:47 PM
P: 9
1. The problem statement, all variables and given/known data
Can someone help me?


2. Relevant equations
Fg=mg
fnet=ma


3. The attempt at a solution
.
1. The problem statement, all variables and given/known data



2. Relevant equations



3. The attempt at a solution
Phys.Org News Partner Science news on Phys.org
Fungus deadly to AIDS patients found to grow on trees
Canola genome sequence reveals evolutionary 'love triangle'
Scientists uncover clues to role of magnetism in iron-based superconductors
ideasrule
#2
Dec10-09, 06:51 PM
HW Helper
ideasrule's Avatar
P: 2,322
Well, first, do you know what the laws ARE? If you do, it's pretty hard to not know the difference between them.
kjohnson
#3
Dec10-09, 08:50 PM
kjohnson's Avatar
P: 158
Newtons second law is the must common to see and is explained below:
F=ma which just states that the acceleration in a given direction is proportional to the NET force in that direction. If two or more forces act in a given direction find the resultant and that is the net force.

Newtons third law is also encountered and relates to interactions:
It states that every action has an equal and opposite reaction. Really this means that forces are equal and opposite at a boundary. If I push a block i will indeed accelerated it but that block pushes back on me with the same force. This is felt as resistance, the heavier the block I try to push the more force I feel.

Newtons first law just states that a object with mass will maintain its path (and velocity) until a force is applied on it. This applied force causes an acceleration. An acceleration is equal to (change in velocity)/(change in time). Likewise if there is no change in velocity there is no force acting on the object.

stanton
#4
Dec12-09, 06:24 PM
P: 74
Difference between newtons 1st,2nd,and 3rd law? How to know when to use them on a tes

Newton's first law is 'all object will continue to be in their state of rest or of uniform speed in a straight line unless they are compelled to change that state by forces acting on them.'

Second law is 'the acceleration of an object is directly proportional to the net force acting on it and is inversely proportional to its mass. The direction of the acceleration is in the direction of the applied net force.'

The third law is 'Whenever one object exerts a force on a second object, the second exerts an equal and opposite force on the first.'

And this website might help you to understand newton's law.
http://teachertech.rice.edu/Particip...wton/law1.html


Register to reply

Related Discussions
Question: What is the difference between e.m.f. and Potential Difference? Introductory Physics Homework 26
Difference between phase difference and path difference General Physics 5
How to calculate interaural phase difference and interaural time difference ? Introductory Physics Homework 0
Path difference and phase difference. General Physics 3