Forces and Newton's Laws Flashcards
In Physics howis speed measured?
metres per second (m/s)
What is the equation for speed?
SPEED = DISTANCE
—————
TIME
how do you calculate RESULTANT FORCE?
add all the forces acting tin the same direction and subtract all the forces acting in the opposite direction
What is Newton’s First Law?
If the forces on an object are balanced then the object will remain at rest or travel at a constant speed in a straight line.
Anastronaut in deep space has no forces acting on her.Describe her possible motion.
She could be stationary.
Or moving at a steady speed.
What happens objects if the resultant force on the object is not zero?
a resultant force on an object will cause it to accelerate.
what will a forward resultant force cause an object to do?
To speed up
What will a backwards resultant force cause an object to do?
to slow down.
What is acceleration measured in?
m/s2
What is Newton’s second law?
Describes what happens to objects when there is a resultant force. The larger the resultant force the larger the acceleration.
If the resultsnt force acting on an object doubles then the acceleration doubles. What is this reationship called?
Direct proportionality
What happens if the mass of an object increases?
The acceleration gets less.
What is the equation for Newton’s 2nd law?
Resultant Force = Mass x Acceleration
RF = M x a
In Newton’s Second Law, the mass in the equation must be measured in ?
Kilos
In Newton’s Second Law, the mass in the equation must be measured in ?
Kilos
What doe Gravity do?
Causes objects to accelerate or fall towards the centre of the planet.
The strength of gravity depends on 2 factors. What are they?
- the mass of an object (the more massive the planet the stronger the pull of gravity will be
- the distance from the object (the further away an object is from the planet the weaker gravity will be
Gravity acts on objects to produce a force called?
Weight
How is the WEIGHT of an object measured?
w = mg
w is the weight of the object in NEWTONS
m is the mass of the object in kilograms
g is the strength of gravity in m/s2 or N/kg
If an object is near Earth’s surface we can take the strength of gravity to be ?
10 m/s 2
