StartingTask As a pair consider how to test the relationships between either: force and acceleration mass and acceleration force and direction What do you think you would find out?
How are mass, force and acceleration related? Two masses of 1 kg and 4 kg are both subject to the same force, which one will accelerate the fastest? The lower the mass, the greater the acceleration for a specific force. This is why Grand Prix cars get faster as they use up their fuel. Less fuel, means less mass, less mass means greater acceleration.
Newton’s Second Law of Motion “The acceleration of a body is proportional to the resultant force and takes place in the direction of the force.”
F=ma We can express the relationship between force, mass and acceleration using the equation: Force = mass x acceleration F =ma Force measured in Newtons (N) Mass measured in kilograms (kg) Acceleration measured in metres per second per second (ms -2 )
Formula triangles F m aa x Formula triangles help you to rearrange formula. The triangle for the f=ma formula is shown below: Whatever quantity you are trying to find, cover it up and it will leave you with the calculation required. So if you were trying to find mass, m….. …you would cover m up… …and you are left with the sum… m = F a
Lesson Tasks Complete the unbalanced forces and acceleration worksheet. Extension: First indivdually and then pairs and finally as tables consider the forces and motion questions.
Homework Prepare for the Newton’s II practical. Read the instructions. Construct a suitable table. Consider in advance any reasons why this experiment may not be accurate. Note: Your preparation has an impact on your performance in experiments grade (Criteria F)
Base Units Note 1 N = 1 kg x 1 ms -2 1 N = 1 kg ms -2 N = kg ms -2 (This is how force is related to the base units)