9k: Speeding Up

The result of unbalanced forces is the
1. resultant force
2. friction force
3. gravitational force
4. push force
Pushes and pulls are all
1. forces
2. friction forces
3. equal
4. unbalanced
If two forces are equal and opposite we say they are
1. balanced
2. unequal
3. unbalanced
4. happy
In a bridge all the forces must be …………………..if the bridge is to stay standing
1. balanced
2. unequal
3. unbalanced
4. happy
If the forces on an object are balanced then the objects movement will
1. remain constant
2. increase in speed
3. decrease in speed
4. it's impossible to tell
Which force slows a falling parachutist?
1. Air resistance
2. Gravity
3. Weight
4. push force
Which of these is not a unit of speed?
1. cm
2. m/s
3. mph
4. km/h
Which of these is not a unit of distance?
1. s
2. cm
3. km
4. m
Which of these is not a unit of time
1. m
2. s
3. hr
4. min
The pre-fix Kilo or K as in Kilometre (Km) means
1. 1000
2. 100
3. 10
4. 1,000,000
The scientific word for speeding up is
1. accelerating
2. decelerating
3. speeding up
4. fastening
The scientific word for slowing down is
1. decelerating
2. accelerating
3. slowing
4. braking
When things move, the air rubs against it. This is called
1. air resistance
2. gravity
3. heat
4. decelerating
Another word for air resistance is
1. drag
2. gravity
3. heat
4. streamlining
Objects which travel through the air easily are said to be
1. streamlined
2. lucky
3. hot
4. fast
If the thrust on an object is 16N and the drag is 8N what is the resultant force?
1. 8N
2. 24N
3. 2N
4. 128N
How is the friction between a hovercraft and the water reduced?
1. It sits on a cushion of air
2. It is oiled around the bottom
3. The craft has a very powerful engine
4. The craft is very lightweight
When a space shuttle re-enters the Earths atmosphere it gets very hot because
1. the particles in the air bash very hard against the surface which causes friction and heats it up
2. the speed of the shuttle makes it get hot
3. the air is hotter near space because it is nearer to the sun
4. it doesn't really get hot, it's only like that because of the sunset
On a speed-time graph what would the line look like if the object was accelerating?
1. Sloping up wards
2. Sloping downwards
3. Flat
4. Some upward and some downward movement
A constant speed on the speed time graph would be shown by
1. a flat line
2. a line sloping upwards
3. a line sloping downwards
4. a line which goes up and down
Forces are balanced when
1. they cancel each other out
2. they are unequal
3. they are equal
4. they are equal but not opposite
The distance it takes for a car to slow down is called the
1. braking distance
2. slowing distance
3. decelerating distance
4. slowing area
Acceleration is
1. the rate at which an object speeds up
2. the rate at which an object slows down
3. the size of the force on an object
4. the difference between the thrust and drag
Friction is
1. the force when two substances rub together
2. the force that stops two substances rubbing together
3. the size of forces opposing each other
4. the way forces resist each other
Gravitational force is
1. the force that prevents things from rubbing against each other
2. the force of repulsion between two objects
3. the force that prevents the Earth from floating off into space
4. the force that prevents us from floating off the Earth
A lever is a simple
1. machine
2. force
3. load
4. movement
If two forces are unbalanced then the object
1. will change direction or speed
2. will change its direction but not its speed
3. may change its direction and speed depending on how long the forces are applied
4. will be unaffected in terms of its direction and speed
The upthrust is
1. the upward force produced on an object in gases and liquids
2. the way that rockets can escape the Earths atmosphere
3. the effect on objects that are high up
4. the effect that stops objects from lifting up.
A parachute is designed to
1. increase the drag on a skydiver and slow their descent
2. reduce the drag on a skydiver to allow them to fly better
3. reduce the speed of a skydiver by making them fly upwards when the parachute is pulled
4. decrease the time the skydiver is in the air so they can go up and jump again