Review

Drag and drop the runners
on the track below to show:

a) constant velocity b) acceleration

 

Drag and Drop Displacement

 

Video Instruction

showmethephysics.com

 

Fill in the Blanks Notes

 

E. Solving Problems using the motion equations

 

Ex 3) Starting from rest, an object accelerates at a rate of 12 m/s2. What is the velocity of the object at the end of 3.0 seconds?

 


 

 

Motion Map

 

 

1st sec / 2nd sec / 3rd sec

12 m/s  / 24 m/s / 36 m/s

 

 

 

Ex 3) Starting from rest, an object accelerates at a rate of 12 m/s2. What is the velocity of the object at the end of 3 seconds?

 

Vi = 0 (Starting from rest)

a = 12 m/s2

Vf = ?

t = 3.0 seconds

 

a = (Vf - Vi)/t

 

12 m/s2 = (Vf - 0)/3.0 secs

(Cross Multiply and Solve)

 


Vf = 36 m/s

 

 

 

 

Ex 4) An object at 100. m/s accelerates at a rate of 120. m/s2. What will the velocity of this object be after .10 seconds?

 

Underline Info

 

 

Ex 4) An object at 100. m/s accelerates at a rate of 120. m/s2. What will the velocity of this object be after .100 seconds?

 

a = (Vf - Vi)/t

 

120. m/s= (Vf - 100. m/s)/.100 s

 

• Cross Multiply

 

12.0 = (Vf - 100.)

 

 

Vf = 112 m/s

 

 

 


3 ways to have non-zero acceleration

 

 

(to change velocity):

 

Speed Up

 

• Slow Down

 

• Change Direction

 

 

 

F. Motion Terms and Direction

A whole branch of mathematics is required to deal with numbers that have direction

 

Trigonometry


This is why it is important to know
which motion information has direction

 

Vector - a quantity that includes magnitude (a number) & direction

 

ex) displacement, acceleration, velocity

 

 

Scalar - a quantity that includes magnitude (a number) only

 

 

ex. time, distance, speed

 

 

 

Invisible Flame

Relight a Candle from Afar

Show Me The Physics YouTube Channel

 

 

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