# Lesson 1: Velocity and Acceleration

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Lesson 1: Velocity and Acceleration
P2 – Forces and Motion Lesson 1: Velocity and Acceleration

Lesson Objectives To know the difference between speed and velocity.
To be able to calculate speed. To be able to calculate acceleration.

Speed and Velocity What is meant by the terms: Speed? Velocity?
To know the difference between speed and velocity. To be able to calculate speed. To be able to calculate acceleration. Keywords: Speed, Velocity, Acceleration, Speed and Velocity What is meant by the terms: Speed? Velocity? is just how fast you are going with no regard to the direction. Must have the direction specified as well as the speed.

Speed and Velocity Are these examples of speed or velocity? So:
To know the difference between speed and velocity. To be able to calculate speed. To be able to calculate acceleration. Keywords: Speed, Velocity, Acceleration, Speed and Velocity Are these examples of speed or velocity? So: Speed and velocity are both measured in the same units and say how fast you are going. Velocity though gives you the direction too. 30 mph Speed 30 km/h north Velocity 15 cm/s Speed 10 m/s, 0600 Velocity

Speed and Velocity Remember: Speed is measured in mph, km/h, m/s, cm/s
To know the difference between speed and velocity. To be able to calculate speed. To be able to calculate acceleration. Keywords: Speed, Velocity, Acceleration, Speed and Velocity You need to be able to calculate the speed of an object. What do you need to know? (think about the units of speed). How far something has travelled - distance How long it took to travel that distance – time. Remember: Speed is measured in mph, km/h, m/s, cm/s

Speed and Velocity d t s So the formula to work out speed is:
To know the difference between speed and velocity. To be able to calculate speed. To be able to calculate acceleration. Keywords: Speed, Velocity, Acceleration, Speed and Velocity So the formula to work out speed is: Remember: Speed is measured in mph, km/h, m/s, cm/s So the answer is in the units: Distance = Speed Time d t s

Speed and Velocity d t s So the formulas are: Speed = Distance Time
To know the difference between speed and velocity. To be able to calculate speed. To be able to calculate acceleration. Keywords: Speed, Velocity, Acceleration, Speed and Velocity So the formulas are: Speed = Distance Time d t Time = Distance Speed s Distance = Speed x Time

Speed and Velocity d t s Lets use the formulas:
To know the difference between speed and velocity. To be able to calculate speed. To be able to calculate acceleration. Keywords: Speed, Velocity, Acceleration, Speed and Velocity Lets use the formulas: A cat walks 20m in 35s. Find: Its speed How long it takes to walk 100m d t s 1a. Speed = Distance = 20m Time s Answer: 0.57 m/s (remember units)

Speed and Velocity d t s Lets use the formulas:
To know the difference between speed and velocity. To be able to calculate speed. To be able to calculate acceleration. Keywords: Speed, Velocity, Acceleration, Speed and Velocity Lets use the formulas: A cat walks 20m in 35s. Find: Its speed How long it takes to walk 100m d t s 1b. Time = Distance = m_ Speed m/s Answer: 175s (remember units)

Speed and Velocity d t s Lets use the formulas:
To know the difference between speed and velocity. To be able to calculate speed. To be able to calculate acceleration. Keywords: Speed, Velocity, Acceleration, Speed and Velocity Lets use the formulas: To calculate velocity, we use the same formula. All that we would need to add is the direction that the cat was walking. d t s

To know the difference between speed and velocity. To be able to calculate speed. To be able to calculate acceleration. Keywords: Speed, Velocity, Acceleration, Task Answer the questions for you given number (6 questions).

Acceleration What is meant by the term: Acceleration?
To know the difference between speed and velocity. To be able to calculate speed. To be able to calculate acceleration. Keywords: Speed, Velocity, Acceleration, Acceleration What is meant by the term: Acceleration? Is how quickly something is speeding up. (i.e. how quickly velocity is changing) It is not the same as speed and velocity.

Acceleration  v t a So the formula to work out acceleration is:
To know the difference between speed and velocity. To be able to calculate speed. To be able to calculate acceleration. Keywords: Speed, Velocity, Acceleration, Acceleration So the formula to work out acceleration is: Change in velocity = Acceleration Time Taken v = change in velocity  v t a

Acceleration Units What are the units for acceleration?
To know the difference between speed and velocity. To be able to calculate speed. To be able to calculate acceleration. Keywords: Speed, Velocity, Acceleration, Acceleration Units What are the units for acceleration? Change in velocity = Acceleration Time Taken Velocity is m/s Time is s So: m/s s Answer: m/s2

Acceleration  v t a Lets see if we can use the formula:
To know the difference between speed and velocity. To be able to calculate speed. To be able to calculate acceleration. Keywords: Speed, Velocity, Acceleration, Acceleration Lets see if we can use the formula: A bike accelerates steadily from 2m/s to 6m/s in 5.6s. Find the acceleration: v = 6m/s – 2m/s = 4m/s a = ? T = 5.6s So: Acceleration =  Velocity = 4m/s Time Taken s Answer: 0.71 m/s2  v t a

Questions a. Find the speed of the mouse which hobbles 3.2m in 35s.
To know the difference between speed and velocity. To be able to calculate speed. To be able to calculate acceleration. Keywords: Speed, Velocity, Acceleration, Questions a. Find the speed of the mouse which hobbles 3.2m in 35s. b. Find how far it will get in 25 minutes. 2. A speed camera is setup in a 30mph (13.4 m/s) zone. It takes two photographs 0.5s apart. A car travels 6.3m between the two photographs. Is the car breaking the speed limit? 3. What is the acceleration of a coin flicked from rest to a speed of 14m/s in 0.4s? 0.09m/s 137m No (12.6m/s) 35m/s2

To know the difference between speed and velocity. To be able to calculate speed. To be able to calculate acceleration. Keywords: Speed, Velocity, Acceleration, Task Answer the questions for you given number (6 questions).

Are you now able to…. To know the difference between speed and velocity. To be able to calculate speed. To be able to calculate acceleration. Keywords: Speed, Velocity, Acceleration, I still feel unsure. I need some more help to understand. I feel ok. I need to do some more work to check my understanding. I am happy and feel I understand and can explain the main points.

To know the difference between speed and velocity.
To be able to calculate speed. To be able to calculate acceleration. Keywords: Speed, Velocity, Acceleration, Using only the following materials you need to design and make a run for a marble to travel form your desk to the floor in the longest time. Rules: You can only use paper and sticky tape. You can not touch the marble once it has been released. Your marble MUST reach the floor. Marks: You will be ranked in time order. Video