Physics 100

What is the relationship between work done, force and distance moved?

Work done \= Force x distance moved

What are the units of work?

Joules (J)

What are the units of energy?

Joules (J)

What are the units of distance?

Metres (m)

What are the units of force?

Newtons (N)

What scientific law states that energy cannot be created or destroyed?

The law of conservation of energy

What is the relationship between gravitational potential energy, mass, gravitational field strength and height?

Ep \= mgh (gravitational potential energy \= mass x gravitational field strength x height)

What is the definition of a vector quantity?

A quantity with size (magnitude) and direction

What is the definition of a scalar quantity?

A quantity with size (magnitude) only

What are the units of speed (or velocity)?

Metres per second (m/s)

What is the relationship between kinetic energy, mass and velocity?

Ek \= 1/2 mv2 (Kinetic energy \= 0.5 x mass x velocity squared)

What is the efficiency equation?

Efficiency \= useful output/total input (energy or power)

What type of energy is stored in a stretched spring or rubber band?

Elastic potential energy

Rearrange the power equation for time

time \= energy transferred / power

What is the relationship between power, energy transferred and time?

Power \= energy transferred / time

What unit is equivalent to 1 Joule per second?

Watt (W)

What are four non-renewable energy resources?

oil, coal, gas, nuclear

What are five renewable energy resources?

Any five: wind, bio-fuel, hydroelectric, geothermal, tidal, Solar, wave

When is the speed of a comet at a minimum?

When it is furthest from the Sun

The temperature of the Suns is 6000K. What does the K stand for?

Kelvin

When is the speed of a comet at a maximum?

When it is closest to the Sun

What is a black hole?

A region of space which is extremely dense, the most dense area of the universe

What two possible outcomes could exist after a supernova explosion?

A black hole or a neutron star

Which star follows a white dwarf?

A black dwarf

Which star follows a planetary nebula?

White dwarf

Which star follows a red giant?

Planetary nebula

Which star follows a main sequence star, for stars similar size to our Sun?

Red giant

What reaction allows stars to emit light?

Nuclear fusion

What is a protostar?

A collapsed nebula

What is a nebula?

A cloud of gas and dust

What is a supernova?

An exploding star which can outshine a whole galaxy

What colour is the coolest star, yellow or blue?

yellow

What colour is the hottest star, red or blue?

Blue

The temperature of the Suns is 6000K. What does the K stand for?

Kelvin

When is the speed of a comet at a minimum?

When it is furthest from the Sun

When is the speed of a comet at a maximum?

When it is closest to the Sun

What is a black hole?

A region of space which is extremely dense, the most dense area of the universe

What two possible outcomes could exist after a supernova explosion?

A black hole or a neutron star

Which star follows a white dwarf?

A black dwarf

Which star follows a planetary nebula?

White dwarf

Which star follows a red giant?

Planetary nebula

Which star follows a main sequence star, for stars similar size to our Sun?

Red giant

What reaction allows stars to emit light?

Nuclear fusion

What is a protostar?

A collapsed nebula

What is a nebula?

A cloud of dust and gas

What is a supernova?

An exploding star which can outshine a whole galaxy

What colour is the coolest star, yellow or blue?

yellow

What colour is the hottest star, red or blue?

blue

What do we call the temperature at which a substance changes from solid to liquid?

Melting point

What do we call the temperature at which a substance changes from liquid to gas?

Boiling point

When a substance is heated, if its temperature rises, what type of energy do its particles gain?

Kinetic energy

What happens to the density of a fluid as it gets hot?

It decreases

What happens to the density of a fluid as it cools down?

It increases

What are the units of "activity" for a radioisotope?

Becquerel (Bq)

What are the three types of ionising radiation?

Alpha, beta, gamma

What is the structure of an alpha particle?

2 protons and 2 neutrons

What is the structure of a beta particle?

1 electron

Which type of ionising radiation is the most ionising?

Alpha

Which type of ionising radiation is the most penetrating?

Gamma

What do we call the average time it takes for half of the nuclei in a radioactive sample to decay?

Half-life

What type of ionising radiation is most commonly used for thickness monitoring?

Beta

What is the penetrating ability of each type of ionising radiation in air?

Alpha \= 5 cm, beta \= 1 m, gamma \= unlimited

What type of ionising radiation is most commonly used for tracers in medicine?

Gamma

What type of ionising radiation is most commonly used in household smoke detectors?

Alpha

What do we call the process of exposing an object to nuclear radiation?

Irradiation

What do we call the unwanted presence of materials containing radioactive atoms on other materials?

Contamination

What process splits large nuclei into two daughter nuclei and 2 or 3 neutrons?

Nuclear fission

What process joins two light nuclei to form a heavier nucleus?

Nuclear fusion

What is the difference between a vector and a scalar?

Vectors have magnitude and direction. Scalars only have magnitude.

What are three examples of non-contact forces?

Gravitational , electrostatic and magnetic forces.

What type of force opposes the motion of an object?

Friction (or drag)

What are typical walking, running and cycling speeds?

Walking - 1.5 m/s, Running - 3 m/s, Cycling - 6 m/s

What is the approximate speed of sound in air?

330 m/s

What is the relationship between resultant force, mass and acceleration?

Resultant force \= mass x acceleration

What is the relationship between weight, mass and gravitational field strength?

Weight \= mass x gravitational field strength

What is the relationship between speed, distance and time?

Speed \= distance/time

How can you determine the speed from a distance-time graph?

Gradient \= speed

How can you determine the acceleration from a velocity-time graph?

Gradient \= acceleration

How can you determine the distance travelled from a velocity-time graph?

Area under the curve \= distance travelled

How can you determine the acceleration at a certain time from a velocity-time graph that has a curved line?

Find the gradient of a tangent line

What are the units for acceleration?

m/s2 (metres per second squared)

What are the units for momentum?

kg m/s (kilogram metres per second)

What do we mean by the word " vacuum " as used in a vacuum flask?

A region of space with no particles

Why do birds ruffle their feathers when the weather is cold?

To trap air as air

What do we call the frictional force experienced by an object falling through air?

Air resistance (or Drag)

What is the term used to describe a falling object when the weight is balanced by the air resistance?

Terminal Velocity

What do we call the point on a force-extension graph when the graph begins to curve?

Limit of proportionality

What is the relationship between thinking distance, braking distance and stopping distance?

Stopping distance \= Thinking distance + Braking distance

Which type of wave oscillates parallel to the direction of energy transfer?

Longitudinal

Which type of wave oscillates perpendicular to the direction of energy transfer?

Transverse

What is the definition of wave speed?

The distance travelled by the wave per second

What is the definition of frequency?

The number of cycles per second

Which electromagnetic wave is used to check luggage at an airport?

x-rays

Which electromagnetic wave is used to tan the skin on a sun bed?

Ultra-violet

Which electromagnetic wave can bounce off the ionosphere so is used to transmit information across a country?

radio

Which electromagnetic wave is emitted by a space satellite?

microwaves

Which electromagnetic wave is emitted by a mobile phone?

microwaves

Which electromagnetic wave is emitted by a toaster?

Infra-red

List the waves of the electromagnetic spectrum in order of increasing frequency

radio, microwave, infrared, visible, ultra-violet, x-ray, gamma

What is the relationship between wave speed, frequency and wavelength?

(Wave) speed \= frequency x wavelength