Forces Flashcards
What is Newton’s first law
If an object is moving or at rest it will remain as it is unless it is acted upon by another force
What is Newton’s second law
When the forces on an object are unbalanced then there is a resultant force which will cause acceleration or deceleration
What is Newton’s third law
Every force will have an equal and opposite reaction
What is Newton’s first law sometimes referred to as
The law of inertia
What is the gravitational force on earth
10
How do you calculate weight on earth
Weight(N)=mass(kg) x 10
What is Hooke’s law
If an object obeys Hooke’s law then the force applied would be proportional to it’s extension until the limit of proportionality
How do you calculate the force of an object that obeys Hooke’s law
F=ke
force=spring constant x extension
How do you workout force
Force(N)=mass(kg) x acceleration(m/s squared)
How do you calculate Stopping Distance
Stopping distance=Thinking distance + Braking distance
How do you calculate Braking distance
Braking distance=Distance the car travels while the brakes are on
How do you calculate the Thinking distance
Thinking distance=Distance travelled while reacting to the situation
How do you calculate reaction time
Time taken to make the decision to break
How can the thinking distance be increased
alcohol, drugs and tiredness
How can the braking distance be increased
weather(wet roads), condition of tires and condition of breaks
What is terminal velocity
When the air resistance is equal to the size of the weight
On a force diagram what does the size and the shape of the arrows show
The longer the arrow the greater the force
The direction the arrow is pointing is the direction in which the force is acting
What happens if one of the arrows is longer than the other
Then the forces are unbalanced and there is a resultant force
What types of contact forces are there
Pull, tension, compression, lift, thrust, friction, upthrust and air resistance
What types of non-contact forces are there
Weight, electric and magnetic
