Quiz 6 Flashcards
What does a curved line becoming less steep on a distance-time graph show?
Slowing down
What does initial mean?
At the start
State 3 factors(apart from speed) which can increase braking distance
Wet/icy conditions, heavier mass and poor condition of brakes or tyres
Complete this sentence:The steeper the line on a velocity time graph
The greater the acceleration
State the speed of a light in a vacuum
300,000,000 m/s
As an object fall its acceleration decreases. Why?
Air resistance increases as speed increases so resultant force decreases
State the unit of displacement
Metres or m
Complete this sentence: The steeper the line on a distance-time graph
The faster the speed
What is newtons 1st law?
An object continues at a constant velocity unless a resultant force acts on it
When an object’s velocity and acceleration are in opposite directions, what happens to the objects motion?
Slows down
What is thinking distance
The distance a vehicle travels during the drivers reaction time
Which is the only factor which affects both thinking and braking distance?
Speed
State the typical value of speed for a person walking
1.5m/s
state the equation linking mass,velocity and momentum
P=mv
State the typical value of speed for a person cycling
6m/s
Eventually a falling object will reach terminal velocity. Why?
Air resistance= weight, zero resultant force reaches 0 so no acceleration
State the typical value of speed for sound in air
330m/s
Define inertia
The tendency of objects to continue in their state of rest or uniform motion
Why do tiredness,drugs,alcohol and distraction increase thinking distance?
They increase reaction time
State 4 factors(apart from speed) which can increase reaction time and therefore thinking distance
Tiredness,drugs,alcohol and distractions
