science deck Flashcards
Give three examples of contact and non-contact forces
Contact:
- Friction
- Reaction
- Air resistance
Non-contact:
- Magnetism
- Gravity
- Lift
What are balanced forces?
Forces that are the same size in the OPPOSITE direction
What is a force?
A push or a pull
Can you see a force?
No
What unit is force measured in?
Newtons
What can be used to measure forces?
A Newtonmeter
A 300N force to the left and a 300N force downward is applied, are these balanced?
No.
What happens to the air resistance as speed is increased?
It is also increased
What is a resultant force?
The force acting overall on an object and specifies a direction.
What is the formula for speed?
Speed=distance/time
If the question doesn’t specify, what should be the default units for SPEED, DISTANCE and TIME?
Speed: m/s
Distance: metres
Time: seconds
What is the speed-distance-time triangle?
/d\
/—–\
/s | t \
dem keyboard skills doe
If there is a straight line on a distance-time graph, what does it show?
The object is stationary.
How do you calculate the speed of an object based on a distance-time graph?
You get the change in y axis and divide it by the x axis
Line A & B are two lines, Line B is steeper, which line shows the object at a faster speed?
Line B
What is the difference between speed and veloctiy?
Speed just shows how fast something is going whilst veloctiy specifies the direction
If the velocity of an object is -1m/s, which direction is it travelling in?
Backwards
What is the equation for pressure?
Force/surface area
What is 1 Pa equal to?
1N/m^2
What is the name of a fixed point that an object roates around?
A pivot
What is the equation for a moment?
Distance from pivot * force
What unit of force are moments measured in?
Newton metres (Nm)
When are moments balanced?
When the clockwise and anti-clockwise moments are equal
What is a spring constant measured in?
Nm^-1
