- Forums
###### F=ma

Watch

2 years ago

Does Newton’s Second Law only apply for particles with constant acceleration?

Also, I’m struggling to understand constant acceleration vs non-constant acceleration. How do we represent and imply non-constant acceleration, since (I think) the acceleration is changing with time.

Also, I’m struggling to understand constant acceleration vs non-constant acceleration. How do we represent and imply non-constant acceleration, since (I think) the acceleration is changing with time.

Reply 1

2 years ago

Original post by NaBrO

Does Newton’s Second Law only apply for particles with constant acceleration?

Also, I’m struggling to understand constant acceleration vs non-constant acceleration. How do we represent and imply non-constant acceleration, since (I think) the acceleration is changing with time.

Also, I’m struggling to understand constant acceleration vs non-constant acceleration. How do we represent and imply non-constant acceleration, since (I think) the acceleration is changing with time.

Newton's Second Law acts on particles when they are accelerated, apart from constant or non-constant. A force generally works when an object is in acceleration.

Acceleration is constant when the velocity is constant too. Whenever velocity has no consistent change according to the changing time, the acceleration can't betoo. Acceleration and velocity are connected.

(edited 2 years ago)

Original post by NaBrO

Does Newton’s Second Law only apply for particles with constant acceleration?

Also, I’m struggling to understand constant acceleration vs non-constant acceleration. How do we represent and imply non-constant acceleration, since (I think) the acceleration is changing with time.

Also, I’m struggling to understand constant acceleration vs non-constant acceleration. How do we represent and imply non-constant acceleration, since (I think) the acceleration is changing with time.

No.

f = ma

applies when the force f varies, constant, zero, ...

When a constant force is applied to a particle, this produces a constant acceleration f/m. Then all the usual suvat equations apply. So vertical motion with only a (constant) gravitational force would produce a constant acceleration scenario.

When the force varies (with time), you have to use calculus (integration) to solve for the velocity and position as

acceleration = dv/dt = d^2 x/dt^2

So integrate f/m once to get the velocity, v, and twice to get the displacement x, This reduces to suvat equations when f is constant. If you also included a velocity (time) dependent drag into the previous vertical motion scenario, then acceleration would not be constant and you'd have to use calculus to solve the problem.

When f is zero, Newton 1 (inertia) applies and the current motion is unchanged. This is Newton 2 with f=a=0.

(edited 2 years ago)

F=ma

Even if a=0 you can still use the formula.

Acceleration is how much the velocity of an object changes every second.

For instance, an acceleration of 3 m.s-2 means that every 1 second, the velocity of the object increases by 3 m.s-2; in other words, the object is speeding up.

Accelation = 0 if the velocity of the object is not changing, ie, a stationary object and an object moving at a constant speed have no acceleration.

Uniform acceleration means that the velocity increases by equal amounts every 1 second. Although acceleration is constant, velocity is increasing.

The same can be said for negative acceleration, when velocity is decreasing

Even if a=0 you can still use the formula.

Acceleration is how much the velocity of an object changes every second.

For instance, an acceleration of 3 m.s-2 means that every 1 second, the velocity of the object increases by 3 m.s-2; in other words, the object is speeding up.

Accelation = 0 if the velocity of the object is not changing, ie, a stationary object and an object moving at a constant speed have no acceleration.

Uniform acceleration means that the velocity increases by equal amounts every 1 second. Although acceleration is constant, velocity is increasing.

The same can be said for negative acceleration, when velocity is decreasing

- Physics help
- A level maths help!!!!
- Mechanics help
- A/S level math question.
- IGCSE Physics - Momentum and Impulse
- Physics question acceleration
- forces in equilibrium and resultant forces
- Pulleys - find k
- Find magnitude of third force
- M1 Dynamics and Moments Question Help
- Essential GCSE physics 13.10 - Isaac Physics
- Types of force acting at once- show mass is 440kg
- AS level Mechanics help-pulleys
- AS mechanics question (maths)
- M1 question - help pls :$
- AS Level Mechanics Question
- Help
- Help mechanics urgent
- connected particles
- A Level mechanics question help

- What unis should I apply to
- Official Dental Hygiene and Therapy (Oral Health Science) 2024 Entry Thread
- English literature paper 1
- Does anyone ever feel like their mother hates them
- Imperial Mechanical Engineering Interview
- CPS Pupillage/Legal Trainee Scheme 2024 (2025 Start)
- UCL Medicine A100 2024
- What YouTube tutorial channels do you watch?
- Unsure of where to go to, any insight if possible would be greatly appreciated!
- Shell Graduate Scheme 2024
- 2024-25 mrc lid
- Official Oxford 2024 Postgraduate Applicants Thread
- Mpharm kcl & ucl
- alevel languages
- Latymer upper vs Upton Court Grammer school
- Latymer upper vs Upton Court Grammer school
- Korean Studies Sheffield
- Airbus degree apprenticeships 2024
- Ulster Univeristy Paramedic Science Bsc
- A level choice medicine

- Plovdiv medical university 2024
- Official: King's College London A100 2024 Entry Applicants
- LATYMER upper 90% bursary VS Upton Court Grammer School please
- Official Cambridge Postgraduate Applicants 2024 Thread
- UNIQ 2024 Cohort
- City of London Academies Highgate Hill (Islington) and Shoreditch Park (Hackney)
- Official: Hull York Medical School A100 2024 Entry Applicants
- Official: University of Bristol A100 2024 Entry Applicants
- 2024 UK Drama School Auditions
- Apprenticeships in medicine
- Motivating myself - my GYG blog :)
- A Level Ancient History 30 mark essays
- TSR BookChat
- Clearing Uni
- science GCSE help
- CTAM: Count to a million (Part 79)
- The Official King's College London Applicants for 2024 Entry Thread
- my gcse adventure ⭐
- Official Durham University Offer Holders Thread for 2024 entry
- Official Geology/Earth Science applicants thread 2024

- A-level Physics Study Group 2023-2024
- Isaac Senior Physics Challenge 2024
- Barometric Formula Isaac Physics
- Banked Tracks for Turning Isaac Physics
- How do I study for A Level physics â€˜Explainâ€™ questions?
- Isaac Physics A Vertical Throw
- Mature student studying physics
- Y12 Senior Physics Challenge 2024
- A level physics nuclear question (3)
- uk physics olympiad round 1 2023

- A-level Physics Study Group 2023-2024
- Isaac Senior Physics Challenge 2024
- Barometric Formula Isaac Physics
- Banked Tracks for Turning Isaac Physics
- How do I study for A Level physics â€˜Explainâ€™ questions?
- Isaac Physics A Vertical Throw
- Mature student studying physics
- Y12 Senior Physics Challenge 2024
- A level physics nuclear question (3)
- uk physics olympiad round 1 2023

The Student Room and The Uni Guide are both part of The Student Room Group.

© Copyright The Student Room 2024 all rights reserved

The Student Room and The Uni Guide are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: Imperial House, 2nd Floor, 40-42 Queens Road, Brighton, East Sussex, BN1 3XB