Energy
DOUBLE JEOPARDY
Why is the mass of the substance conserved when it changes state?
The number of particles does not change
What happens to the particles in a substance if its temperature is increased?
They move faster and the energy in their kinetic energy store increases
Equal numbers of positive protons and negative electrons
What is one factor that affects braking distance?
Speed of the vehicle, road conditions or conditions of brakes/tyres
How can we calculate stopping distance?
stopping distance = thinking distance + braking distance
What property of gas is related to the average kinetic energy of its particles?
Temperature
DOUBLE JEOPARDY
Why can't solids be compressed or squashed?
The particles are close together and have no space to move into
What is the atomic number of an element?
Number of protons in one atom of the element
DOUBLE JEOPARDY
What is the difference between distance and displacement?
Distance is a scalar quantity and only has magnitude (size).
Displacement is a vector quantity and has both magnitude and direction.
What two quantities do you need to measure to find the density of a solid or liquid?
Mass and volume
Density = mass/volume
What is specific heat capacity?
The amount of energy needed to raise the temperature of 1kg of a material by 1*C
What is the state change called when a solid -> gas or a gas -> solid?
Sublimation
What is formed if an atom loses an electron?
Positive ion
What are typical speeds for a person walking, running and cycling?
1.5 m/s, 3.0 m/s and 6.0 m/s
What is the name for the force acting on an object due to gravity?
Weight
What causes the pressure of a gas on a surface?
The force of the gas particles hitting the surface
On a graph of temperature against time for a substance being heated up or cooled down, what do the flat (horizontal) sections show?
The time when the substance is changing state and the temperature is not changing
What are isotopes?
Atoms of the same element (same number of protons) with different numbers of neutrons.
What information does the gradient of the line in a velocity-time graph provide?
Acceleration
Which particle do atoms of the same element always have the same number of?
Protons
Give one reason why the pressure of a gas in a sealed container increases if its temperature is increased
The force applied to compress the gas results in work being done to the gas
OR
The energy gained by the gas is not transferred quickly enough to the surroundings
What is kinetic theory?
All matter consists of many, very small particles which are constantly moving or in a continual state of motion
What were the two main conclusions from the alpha particle scattering experiment?
Most of the mass of the atom is concentrated in the nucleus
Nucleus is positively charged
Define inertia
Inertia is the tendency of an object to remain in a steady state.
Newton's First Law says that the velocity, speed and/or direction of an object will only change if a resultant force is acting on it.
What is the resultant force of an object moving at a steady speed in a straight line?
Zero