Forces Flashcards
Is magnetic force a contact or non-contact force?
non-contact force
If the speed at which an object moves through a fluid increases, will the size of the frictional force that acts on it increase, decrease or stay the same?
increase
Is tension a contact or non-contact force?
contact force
Give the general name for the type of quantity that has magnitude and acts in a particular direction.
vector quantity
Is force a vector or a scalar quantity?
vector quantity
Is friction a contact or non-contact force?
contact force
When two objects interact they exert forces on each other. Will these forces act in the same direction or in opposite directions?
opposite
Does Earth exert a contact or a non-contact force on the moon?
non-contact force
Every force on an object is either…
a contact or a non-contact force
Leanne is riding a bike. The forward force from her pedalling is 18N. There is a backward force of 6N from friction and a backward force of 12N from air resistance. Does the speed of the bike increase, decrease or not change?
not change
Is time a vector or a scalar quantity?
scalar quantity
Give the general name for the type of quantity that has magnitude but no particular direction.
scalar quantity
True or false? Forces always act in pairs.
true
Object 1 has a low centre of mass and Object 2 has a high centre of mass. Which object will be more stable?
object 1
True or false? If the vertical line through an object’s centre of mass falls within its base of support then the object will topple over.
false
What name is given to the point at which the mass of an object may be considered to be concentrated?
centre of mass
True or false? Only objects with a symmetrical shape can have a centre of mass.
false
A single force can be resolved into two component forces that act at _____° angles to each other.
90
What name is given to the overall force acting on an object?
resultant force
An object’s mass and its weight are… what?
directly proportional
Jupiter has a gravitational field of 23.6 N/kg. Would your mass be more, less or the same on Jupiter as it is on Earth?
same
Ahmed wants to measure the weight of an object. What instrument should he use?
calibrated spring-balance
True or false? An object weighs less on the moon than it does on Earth.
true
Name the unit which is used for weight.
newtons
Name the universal force of attraction that exists between masses.
gravity
Jupiter has a gravitational field of 23.6 N/kg. Would you weigh more or less on Jupiter than you do on Earth?
more
True or false? An object has the same mass on Earth as it does on Mars.
true
Jupiter’s gravitational field is stronger than Earth’s. On Jupiter, an object’s__________ will be greater than on Earth. What one word completes the sentence?
weight
What is the SI unit for mass?
kilogram
_______ = mass × gravitational field strength
weight
Weight = _____ × gravitational field strength
mass
Weight = mass x ________________ ______ ________
gravitational field strength
Weight is the downward pull of __________ on mass.
gravity
True or false? Weight is a force.
true
What is the main force that must be overcome in order to push an object along a horizontal surface?
friction
Abed uses a force of 1 newton to slide a salt shaker 1 metre across a table. How many newton metres of work has he done?
1Nm
_____ _____ = force × displacement
work done
Work done = ______ × displacement
force
Work done = force × ______________
displacement
How much work is done if a force of 20N is used to move an object 6 metres?
120J
_____ ______ = force × distance
Work done
What is transferred when work is done?
energy
Sara pushed a box of lab equipment along the ground, displacing it by 1 metre. By doing this, she has done __________ on the box of lab equipment.
work
Sara was pushing around a box of lab equipment. She was doing work on it by applying a force and displacing it. Because this work was done against a frictional force that was also acting on the box, the temperature of the box… what?
increased
When a force causes an object to move a distance, __________ is done.
work
What units are used for work done?
joules
When a force causes an object to move, what happens?
work is done and energy is transferred
A force does work on an object when it causes a __________ of the object.
displacement
10 newton metres is equal to how many joules?
10
Work done = _____ × distance
force
Work done = force × ________
distance
Gareth squashed one of his grandma’s favourite cushions as he sat down. True or false? The cushion was squashed by the action of only one force.
false
____ ______ are required to squash an object, otherwise the object would accelerate rather than change shape.
two forces
Two forces are required to squash an object, otherwise the object would __________ rather than change shape.
accelerate
Two forces are required to squash an object, otherwise the object would accelerate rather than change ________.
shape
Johann squeezes a bagel too hard at the supermarket, and it does not return to its original shape when he removes his hand. The bagel has been __________ deformed. What word completes the sentence to show that the bagel has been permanently changed?
inelastically
Inelastic deformation
when an object does not return to its original shape and size when all forces are removed
what’s it called when an object does not return to its original shape and size when all forces are removed
Inelastic deformation
True or false? Objects that can regain their original shapes have energy in their gravitational potential energy stores when their shape is changed by a force.
false
elastic potential energy = ___ × spring constant × (extension)^2
0.5
elastic potential energy = 0.5 × ______ __________ × (extension)^2
spring constant
elastic potential energy = 0.5 × spring constant × _____________
(extension)^2
_______ _________ ________ = 0.5 × spring constant × (extension)2
elastic potential energy
The extension of the spring can be worked out by measuring its __________ when different forces are applied.
length
To work out extension you need to measure the _________ _______ and the final length and find the difference.
starting length
To work out extension you need to measure the starting length and the _______ _______ and find the difference.
final length
_____ = spring constant × extension
force
Force = _________ ________ × extension
spring constant
Force = spring constant × __________
extension
A slinky is stretched by two forces. When the forces are removed, the slinky returns to its original length. The slinky has been __________ deformed.
elastically
True or false? In a non-linear relationship, a change in one variable will always produce a proportional change in the other variable.
false
When you stretch a spring, there is energy in the spring’s __________ potential energy store.
elastic
describe something elastic
return to its original shape and size after being deformed
True or false? In a linear relationship, a change in one variable will always result in a change of the same size in the other variable.
false
Different masses were hung from the spring in order to apply different __________ to it.
forces
Can an object be compressed if only one force is acting on it?
no
The extension of a spring is directly proportional to the __________ applied to it.
force
Doubling the force on a spring will double the __________
extension
Doubling the force on a spring will _______ the extension
double
Doubling the _______ on a spring will double the extension
force
Doubling the force on a spring will double the extension, so they are _______ ___________.
directly proportional
The extension of a spring will increase if the force applied to it… what?
increase
