Forces by name
What is the name of the force that acts through a stretched rope?
tension
What is a typical speed (in m/s) for someone cycling?
6 m/s
What is Newton's third law?
When two objects interact, they exert equal and opposite forces on each other.
What is stopping distance?
What is the gravitational field strength near the surface of Earth?
9.8 N/kg
What do we call the upward force that keeps boats afloat?
upthrust
How should you interpret a flat, horizontal line on a displacement-time graph?
object is not moving
According to Newton's second law, an object will accelerate in which direction?
In the direction of the resultant force on it
What force do brakes use to slow a car?
friction
What is 80 kilometres per hour in metres per second?
22.2 m/s
Which force is the product of an object's mass and the gravitational field strength?
weight
What are the two most important forces acting on an object falling through air?
weight and drag (air resistance)
If an object is not accelerating, what conclusion can be drawn about the forces acting on it?
There is no resultant force (forces are balanced).
What is the relationship between reaction time and thinking distance?
directly proportional
What word describes forces that can only act between objects that are physically touching?
contact forces
Friction is a force that acts in which direction?
opposite to motion
What quantity is represented by the area under a velocity-time graph?
displacement
For a given force, what is the relationship between an object's mass and its acceleration?
inversely proportional
When a car slows down, its kinetic energy is transferred to which energy store of which object(s)?
thermal store of brakes (and surroundings)
State two ways to make an unstable object less likely to topple.
1. Lower the centre of mass
2. Increase the size of the base
What is the name of the force of attraction between objects with opposite charges?
electrostatic force
How can an object accelerate without changing speed?
by changing direction
An object at rest tends to stay at rest; an object in motion tends to stay in motion. What is the name of this tendency?
inertia
Which factor affects thinking distance but not reaction time?
speed of car
Weight can be measured using a calibrated spring-balance. What is the proper name for this instrument?
newtonmeter