P5 Forces - random revision (pages 201 - 216) Flashcards
Give two examples of quantities that have both magnitude and direction.
Any two from e.g.:
force
velocity
displacement
What property does a vector quantity have that a scalar quantity does not?
Direction
Speed and distance are both examples of what type of quantity?
Scalar
Define the term ‘non‑contact force’ and give one example of this type of force.
A force where objects do not need to be touching for the force to act. Any one from e.g.: magnetic force, electrostatic force, gravitational force.
Define ‘weight
The force acting on an object due to gravity.
What quantity is measured using a calibrated spring balance?
Weight
Give the equation that links mass, weight and gravitational field strength.
W=mg/ weight= mass ×gravitational field strength
How could you work out the resultant force created by two forces acting on an object in the same direction?
E.g. add them together
When work is done against friction to move an object, how would the object’s temperature change?
It would increase
State the equation linking the work done by a force with the force and the distance moved along the line of action of the force.
W=Fs/ Workdone= force ×distance(moved along the line of action of the force)
How much work is done when a force of 1newton causes an object to move 1metre?
1joule
Describe how to use a scale diagram to find the size of the resultant force acting on an object.
Draw all the forces acting on the object out ‘tip‑to‑tail’ and to scale. Then draw a straight line from the start of the first force to the end of the last force. This line is the resultant force. Measure the length of the line and use the scale chosen to find the size of the resultant force.
If all the forces acting on an object are drawn out ‘tip‑to‑tail’ in a scale diagram and form a closed shape, what is the size of the resultant force acting on the object?
Zero
Describe how to resolve a force that is acting at an angle into its horizontal and vertical components.
E.g. draw the force to scale on a scale grid at the correct angle and then add horizontal and vertical lines from each end of the force, so they make a right‑angled triangle. The horizontal and vertical components can then be measured and the size of each force determined using the scale of the grid.
Why does more than one force have to act on an object for it to deform?
If just one force acts on an object, it will only cause the object to move, not change its shape.
What type of deformation does an object undergo if it is stretched by forces and does not return to its original shape after the forces are removed?
Inelastic deformation
What does each letter represent in the equationF=ke?
Fis the force,kis the spring constant andeis the extension.
What is the name of the point where the relationship between the force applied to a spring and its extension stops being linear?
Limit of proportionality.
Doing work to stretch an object elastically causes energy to be transferred to which energy store?
Elastic potential energy store
For each of the following, state whether it is a scalar or vector quantity:
displacement
speed
velocity
distance
Displacement−vector
Speed−scalar
Velocity−vector
Distance−scalar
Give an example of a situation where an object is moving with a constant speed but with a velocity that is constantly changing.
E.g. travelling in a circle.