One Dimensional Motion Physics Practice

Neglecting air resistance.  Any mass would take the same time to hit the ground no matter how massive or minute.  Many times a question may say in a vacuum which means there is no air resistance since air particles are sucked out removed from a vacuum.

Acceleration which is the rate at which the (Y axis) velocity on a V/T graph is changing.

In the graph provided the object is going 8 meters every seconds (so is moving) but no slope or acceleration.

Was moving at a constant rate of -4 m/s velocity for 30 seconds or had a constant backward velocity of 4 meters per second.

Slope on a V/T graph is equal to acceleration.  There was no acceleration because the slope was flat, but there was a velocity the whole time.

A straight line means something is constant.  A straight sloped up line on a position time graph meant the position is moving at a constant rate or constant velocity.

On a V/T graphs the slope is acceleration.  The slope here is sloped so there is acceleration.  Another way to think about it is by what is happening in the graph.  The object went 0 m/s to 12 m/s during the 30 seconds.  They sped up during the entire time.

On a P/T graphs the slope is velocity.  The slope here is flat so no velocity.  Another way to think about it is by what is happening in the graph.  The object went from 16 meters to 16 meters in 30 seconds.  Therefore is in the same place and did not move.

The acceleration is always 9.8 m/s² down or averaged to 10 m/s² down.

The ball dropped would have a head start and always be traveling faster downwards

The Y velocity continues to change but is 0 m/s at the top of the flight for an instant.

The acceleration is always 9.8 m/s² down or averaged to 10 m/s² down

How far is displacement or x

the unit is (m/s) so its a velocity but there is acceleration so it is not just v

he is traveling at 16 m/s after accelerating at 2 m/s² so we know the final and the question asks for the initial

v_i = ?

variable: unit (unit variable)

x : meters (m)

v, v_i, v_f : meters/second (m/s)

a: meters/second² (m/s²)

t: (s)

The unit for acceleration is m/s²

The unit defines what the 15 is.  15 what?

meters

What is your displacement after going 10 meters east followed by 20 meters west in 10 seconds?

Displacement is vector and a measure of how far you are from start to finish.  Take into account the direction.

10 m east becomes (+10)

20 m west becomes (-20)

add them together including the sign ((+10) + (-20))

(-10 meters) or 10 meters west

What is your speed after going 10 meters east followed by 20 meters west in 10 seconds?

speed is a scalar so disregard the direction.

v = x/t

(10 meters + 20 meters) / (10 seconds)

15 m/s is a magnitude only but includes a distance over time so is the scalar speed.

15 m is a magnitude and east is a direction.  This is the vector displacement having both magnitude and direction from the origin to the end.

Displacement  is a vector that includes direction. Make the direction a sign (east positive and west negative) before you add (10 + (-3)) =  -7 meters which becomes 7 meters west

Distance is a scalar that has no direction. You do nothing with the direction and just add all the individual magnitudes up (10 + 3) here.

You can't put a direction on the final answer since it is a measure of how far you went totally and not a direction.

You should not put a direction on the final answer either since this is not a measure of where you are located but just how far you went in any direction.