What does the gradient on a distance-time graph represent?
Speed
Acceleration
Distance travelled
Velocity of an object the speed of an object in a given direction
What does the gradient of a velocity-time graph represent?
Distance
Distance travelled by an object can be calculated from a distance-time graph
What is newtons third law?
Every action has an equal and opposite reaction
An object will remain at rest unless acted upon by an external force
The combined effect of all forces acting upon an object is called the...
Resultant force
Drag force
Newton
If the resultant force on an object is zero it will...
remain stationary
accelerate in the direction of the resultant force
If the resultant force on an object is not zero it will...
When a vehicle is driving at a steady speed the resistive forces balance the driving force
What are 3 things that could effect the drivers reaction time?
Drugs
Tiredness
Alcohol
Shoe colour
Diet
Exercise
What happens when brakes are applied on a car...
there is friction between the brakes and the wheel reducing the kinetic energy of the vehicle
the car speeds up
the friction between the brakes and wheels increase the kinetic energy of the car
The __________ an object moves through a fluid the __________ the frictional force that acts on it
Faster, slower
Faster, greater
Slower, greater
when the resultant force of an object is zero it will move at its terminal velocity
What might a force being applied to an object cause?
stretching or squashing
Changing its shape
Changing its volume
Changing its colour
An elastic object can't recover its original shape when stretched
The extension of an elastic object is directly proportional to...
The force applied
The mass of the object
The length of spring
When a force causes an object to move through a distance work is done
In a closed system the total momentum before an event is _______ to the total momentum after an event, what is this called?
Equal, Conservation of momentum
More, conservation of momentum
Equal, conservation of minstrels
Which type of materials rub together to become electrically charged?
Metal
Reactive
Insulating
Conductor
Losing electrons means a material becomes...
Negatively charged
Positively charged
If two objects have the same charge will they repel or attract each other?
Repel
Attract
What is the electrical symbol for a diode?
which is the current-potential difference graph?
which graph shows the current flowing through a diode?
this one
This one
Is the potential difference in a series or parallel circuit the same across each component?
Series
Parallel
Is the current in a series or parallel circuit the same across each component?
series
parallel
The current through a resistor is directly proportional to the potential difference across the resistor
Resistance of an LDR increases as the light intensity increases
What is the a.c. supply in the UK?
230V
230Hz
230
What colour is the live wire?
blue
yellow and green
brown
What colour is the neutral wire?
If the current in a fuse wire gets too high the fuse will melt breaking the circuit
when an electrical charge flows through a resistor so it cools
what is in the nucleus of an atom?
Protons and neutrons
Electrons and neutrons
Electrons and protons
What is the relative charge of a proton?
+1
0
-1
electrons have a relative mass of 0.005
Which rays are most penetrating?
Alpha
Beta
Gamma
Which type of radiation isnt deflected by both electric and magnetic fields?
Half life is the time taken for the number of unstable nuclei in a sample to halve
What are the two fissionable substances?
plutonium 239 and uranium 265
plutonium 239 and uranium 235
The nucleus undergoing fission splits into 2 smaller nuclei and two or three whats are released?
nuclei
electrons
neutrons
Fusion is the joining of two _____?
Neutrons
Electrons
Nuclei
Stars form when what from space is pulled together?
planets and dust
dust and rocks
gas and dust
During the main sequence period of its life cycle the star is stable as the forces are balanced