Mechanics 1

Question 1

Key things about acceleration

Answer 1

If it’s negative velocity and positive, it slows down, is instanekusky staginsry and then starts speeding up

If it is negative and negative going faster, if it is positive nag negtavjve slowing down until zero then fsster

Question 2

Velocity time graoh displacement,emf

Answer 2

Displacement is shown by area, add the top and subtract from bottom to get final disoaldment

Here velocity just means direction, if it positive positive direction, if negative other way but displacement could still be positive

Question 3

Distance time graph, speeding up vis slowing down

Answer 3

This is bith acceleation , and nagtive accerlwtiojn(changing speed in time is accerlwtion)

Thus it curved up ir curved down

Question 4

Converting from distance to velocity to acceleration time graoh

Answer 4

Distance
- where it is accelerating , that means constant acceleration . As gradient vt is acceleration it means CONSTANT GRSDIENT
- where it is grsdient it means constant velocity, so velocity straight ,
- deceleration constantly means grsdient to show accerlwtion and it’s constant. Returns to 0 because it stop moving

Then velocity to accerlwtion, constant grwdient v means constant line

Constant line means no accerlwtion= 0

Question 5

Distance vs displacement on velocity time graoh

Answer 5

Distance is FULL AREA

displacement is one minus the ither

Question 6

First work out distance and what this reprsents then draw graohs to solve, and remember ending nit as easier as you thing,

Question 7

When can suvat equations be used? When

Answer 7

Acceleration is constant thus no drag etc WD thisnid variablem

Question 8

How is this often used as models, what assumption do we make

Answer 8

We make that there is no resistance to which accerlwtion would be variable

That’s why ee model everything as a particle so it’d mass is so small. For injected with very little madd, this is a reasonable model

Question 9

Doing suvat in two parts!

Answer 9

Make sure you use variables for stuff thatsconstant, in bith situwtuons, and make two equations and then you can solve simultaneously

Don’t be a fraud and see if it has travelled 13 m in the 6th second, that means from 5 to 6 it’s travelled 13m!

Question 10

When is modelling with acceleration realistic

Answer 10

Bsdicslly inna flat road and constant pedal

But up a hill is unrealistic due its

Question 11

VERY IMPORTANR, if they say DECELERATION NEED TO PUT IT WITHOUT NEGATJVE!

Answer 11

If put with negative it becomes acceleration! Only negative if it’d acceleration!

Please be careful her