Movement and Forces Flashcards
What is a scalar quantity?
A force with magnitude but no direction.
What is a vector quantity?
A force with magnitude and direction.
Give four examples of scalar quantities.
Speed, mass, distance, temperature.
Give four examples of vector quantities.
Velocity, weight, displacement, acceleration.
What does SUVAT stand for?
Displacement, Initial Velocity, Final Velocity, Acceleration and Time.
What is the gradient of a displacement-time graph?
Velocity.
What is the gradient of a velocity-time graph?
Acceleration.
What is the area underneath a velocity-time graph?
Displacement
If a line is flat in a displacement-time graph, what does it represent?
That the object is stationary.
If a line is flat in a velocity-time graph, what does it represent?
That the object is moving at a constant speed.
What is the average acceleration due to gravity?
g=9.81
What is the center of mass?
The point on an object that is acted on by weight.
Where will the center of mass be for a uniform body?
In the middle.
What is instantaneous velocity?
The velocity of an object at a specific point in time.
What is average velocity?
The velocity of an object over a specific time frame.
What is uniform acceleration?
Where the acceleration of an object is constant.
What is the area underneath an acceleration time graph?
Velocity
What is Newton’s 1st Law?
An object that is at rest or at a constant velocity, will not change until acted upon by a resultant force.
What is Newton’s 2nd Law?
The acceleration of an object is proportional to the force experienced by the object. (AKA F=ma)
What is Newton’s 3rd Law?
For each force experienced by an object, the object exerts an equal and opposite force.
What are the 4 SUVAT equations?
v = u + at s = ½(u + v) x t s = ut + ½at² v² = u² + 2as
How do we resolve a vector?
We split a resultant vector into the x-direction and y-direction.
What’s a free body diagram?
A diagram which uses arrows to show forces on the body’s we are interested in.
What’s the definition of weight?
Weight is the force acting upon an object due to gravity.
How do we know if a pair of forces are obeying Newtons Third Law?
Same type of force.
Same magnitude.
Act on different bodies
Act in opposite directions.
What are coplanar forces?
Where all the forces in a system are acting on the same plane.
What is 1 newton?
1 newton is the force required to accelerate 1kg of mass 1ms⁻² in the direction of the force.
What must be constant for us to use the equation F=ma?
mass