IGCSE physics

Created by

Shreeya Doshi

Cards (277)

non contact forces 
weight, electrostatic force, magnetic force
contact forces
friction, drag, air resistance, tension, normal contact force
scalar quantities
mass, time, speed, temperature, volume, energy
vector quantities 
velocity, acceleration, displacement, weight, momentum, force
what is velocity 
speed in a given direction (m/s)
what is acceleration 
the rate of change of velocity (m/s^2)
what is displacement 
distance in a given direction (m)
what is mass 
the amount of matter in an object (kg)
what is weight 
the force of gravity acting on a mass (N)
what is force measured in
Newtons
what is energy measured in 
Joules
what is the gradient of the line on a distance time graph
speed
what does a horizontal line on a distance time graph show
the object is stationary
what does a straight diagnol line show on a distance time graph
constant speed
what is distance always measured in, in physics
metres (m)
what is time always measures in, in physics
seconds (s)
what does the gradient of a velocity time graph show
acceleration (m/s^2)
what does a horizontal line show on a velocity time graph  
No acceleration, so constant velocity (if v is 0, the object is stationary)
what is the area under a velocity time graph
distance (m)
what is newton's first law 
when resultant force is 0: -If the object is moving, it will continue to do so at a constant velocity. -If the object is stationary, it will stay at rest.
what is newton's second law 
acceleration is directly proportional to resultant force, but indirectly proportional to mass
what is newton's third law
when 2 objects exert the same force on each other, both these forces are equal in magnitude and opposite in direction
what is Hooke's law 
the force applied to a spring is directly proportional to its extension, until the limit of proportionality is reached
what is the limit of proportionality 
when an elastic material has had so much force applied onto it that it can no longer return back to its original shape
what is the spring constant of a spring
how stiff the spring is
Hooke's law practical 
1. Hang a spring and pointer onto a clamp stand
2. Measure and record the initial length of the spring without mass using a ruler (cm)
3. Add a 100g mass hanger onto the spring
4. Measure the length of the spring with mass, using a ruler. Make a record of the mass used and extension of the spring
5. Add another 100g mass hanger, measure and record the total mass used and the extension of the spring
6. Repeat this process until all masses are being used
7. Remove the masses and repeat the whole process about 3 times
8. Calculate an average length
how to find the extension of a spring 
final length - original length
what is the independant variable for the Hooke's law practical
force (total mass being used)
what is the control variable for the Hooke's law practical
the spring constant
what is the dependant variable for the Hooke's law practical
extension
how do forces act when an object is being compressed
forces are in opposite directions towards the object
how do forces act when an object is being stretched
forces are in opposite directions away from the object
how do forces act on an object being bent
multiple forces act in opposite directions, and at different points of the object
what is an elastic distortion
when an object returns to its original shape once stretching force is removed
what is inelastic distortion 
when an object doesn't return to its original shape once stretching force is removed
what is resultant force 
the overall force acting on an object, taking into account both magnitude and direction of all the forces acting on it
what is momentum 
mass x velocity (kgm/s)
what happens to momentum when the direction of an object changes
the sign changes
what is the momentum of a stationary object 
0
what is the conservation of momentum law 
in a closed system, the total momentum before an interaction is equal to the total momentum after