Forces Flashcards
What forces are exerted on each other?
An equal and opposite force is always exerted between 2 objects, measured in newton’s (N), also known as action and reaction forces
What is the resultant force and the results from being on 0?
All the forces added together to give one overall force. If on 0, the object is either stationary or the object is at a constant speed.
What if the resultant force is not 1?
The object will move in the direction of the resultant force, or if it’s going in the opposite direction it will decelerate
What is the equation to find the resultant force and theory behind it?
Resultant Force (N) = Mass(kg) x Acceleration (m/s2)
A resultant force is needed to make an object accelerate or change direction. The greater the acceleration the greater the resultant force and the greater the mass the greater the resultant force needed to budge it. Hence the proportional equation.
What is the stopping distance?
Braking + thinking = stopping
Factors that affect braking = road, car, weather
Factors that affect thinking = alcohol, drugs, distraction
How can mass x acceleration = weight
Weight is the resultant force of gravity (10m/s2) an acceleration. When an object FALLS it’s mass and acceleration deter the weight it falls with.
If a person is just stood on the ground, what force is acting upon them?
Gravitational field strength N/Kg
When falling through air or water, what forces are exerted
A drag force or air resistance is created
This eventually becomes equal to the weight of the object, so it’s mass x acceleration
Now the resultant force is 0
It has reached constant velocity
What happens to an elastic object when weights are put on and taken back off again
It stretches, and the increase in length is called the extension. When we remove the weights it regains it’s original
What’s Hooke’s law?
Force Applied (N) = Spring constant - k (N/m) x extension (m)
The stiffer the spring, the greater it’s spring constant
What is the limit of proportionality
The force exerted is directly proportional to the extension, so when a curve starts to show, the limit of proportionality has been breached and the elasticity has gone
When an elastic band is stretched what is done and what energy transfers take place
Kinetic - Elastic potential - Kinetic
WORK is done
How can fuel economy be improved
Reducing the speed the car travels at
Reducing the air resistance, so making it more streamlined
What are anti-skid surfaces and where are they used
Rougher surface than normal roads to increase the friction so stopping distance is shorter. Used near traffic lights and junctions, help to prevent crashes.
