A Plimsoll Line is
- on a ship
- in a factory
- inside the body of a fish
- part of a telephone system
When we combine forces we get
- a resultant force
- a sum force
- friction
- an object's weight
forces are measured in
- newtons
- kilograms
- metres
- seconds
weight is
- the force of gravity pulling on an object
- the amount of material in an object
- the space occupied by an object
- the density of an object
mass is
- the amount of material in an object
- the force of gravity pulling on an object
- the space occupied by an object
- the density of an object
mass is measured in
- kilograms
- newtons
- metres
- seconds
weight is measured in
- newtons
- kilograms
- metres
- seconds
speed is measured in
- metres per second
- metres
- seconds
- newtons
speed =
- distance / time
- time / distance
- distance x time
- time x distance
if two forces are equal and opposite, we say they are
- balanced
- resultant
- combined
- cancelled
density =
- mass / volume
- volume / mass
- mass x volume
- volume x mass
an object will float in water if
- the upthrust equals the weight
- the upthrust equals the mass
- the upthrust equals the mass
- the upthrust is less than the mass
When forces are balanced, the resultant force is
- zero
- equal to one of the forces
- less than both of the forces
- upwards
Whose "principle" says "when an object floats, the upthrust = the weight of fluid displaced"?
- Archimedes
- Sir Isaac Newton
- Edwin Hubble
- Democritus
When the particles in a structure are pushed together, we say that that part is under
- compression
- tension
- force
- upthrust
A parachutist falls at a constant speed because
- the air resistance equals her weight
- the upthrust equals her weight
- the air resistance is less than her weight
- there is no air resistance
when we stretch a spring,
- the extension doubles when the force doubles
- the length doubles when the force doubles
- the length decreases when the force increases
- the extension is constant
a force that slows objects down, or stops them from moving, is often called
- friction
- upthrust
- weight
- resultant
friction can be reduced by
- lubrication
- pressing the surfaces together
- increasing the speed
- roughening the surfaces
when a toy car runs down a ramp,
- gravitational potential energy is transferred to kinetic energy
- kinetic energy is transferred to gravitational potential energy
- kinetic energy is transferred to chemical energy
- kinetic energy is made
for a vehicle, stopping distance equals
- thinking distance + braking distance
- thinking distance
- braking distance
- braking distance - thinking distance
if a road is wet, the braking distance for a vehicle
- increases
- decreases
- is the same as for a dry road
- is less than for a dry road
if a road is wet, the thinking distance for a vehicle
- is the same as for a dry road
- increases
- decreases
- is less than for a dry road
on a distance-time graph, a steep line means
- the object is moving fast
- the object is moving slowly
- the object is not moving
- the object is moving backwards
on a distance-time graph, a flat line means
- the object is not moving
- the object is moving fast
- the object is moving slowly
- the object is moving backwards
on a distance-time graph, a line sloping downwards means
- the object is moving backwards
- the object is moving slowly
- the object is moving fast
- the object is not moving
the "gradient" of a graph means
- the slope
- the distance along the x-axis
- the distance along the y-axis
- that the graph is a straight line
if an object is "streamlined", it means that it
- moves easily through the air or water
- creates turbulence as it moves
- has a high air resistance
- has been tested in a wind tunnel
distance-time graphs are plotted as
- line graphs
- bar charts
- pie charts
- column charts
a famous scientist who experimented with stretching springs was
- Robert Hooke
- Isaac Newton
- Albert Einstein
- Marie Curie