Forces and Energy Flashcards
What is a earthquake
Movement in earths Tectonic Plates resulting in large amounts of energy releases
What are the effects of an earthquake on earths surface
Tremors and Fissures
Land slips
Avalanches
What are typhoons
strong wind and heavy wind causing flooding. Wind can reach 200 km/h
How do typhoons affect earth crust
Strong gusty wind
Floods
What are volcanic eruptions
Large amounts of energy released from earth as heat, light and kinetic energy of the magma
What does volcanic eruption do to the earths surface
eruption of magma
Deposition of debris caused by magma
What is a force
A force is a push or pull upon an object resulting from the objects interaction with another object.
What is the force SI unit
N [ newtons ] all caps
Tell me the equation of weight
Weight = mass x speed caused by gravity
What is gravitational force
it is the force exerted by a planet on an object. Known as the weight of the object
Is gravitational force a contact force or non contact
Non contact because gravitational force still pulls objects towards the centre of the earth without the need of physical contact
So what is weight
it is the amount of gravitational force acting on our body
So when we are bigger in size why are we heavier?
There is more surface area of our body coming into contact with gravitational force causing gravitational force to act on us more.
What is magnetic force
Push or pull force exerted by a magnet only
Is magnetic force contact or non contact
Non contact as he magnets need not touch in order for a push and pull force to be exerted. The push and pull force is produced but not needed in order to produce a force
What is contact force
Forces that result when two interacting objects are perceived to be physically contacting each other.
What is a non contact force
Forces that occurs even when two objects are not in physical contact with one another
What is electrostatic force
Force that exists between charged particles specifically ions
Is electrostatic force contact or non contact
Non contact as force is exerted even if there is no physical contact between two object
What is frictional force
force exerted by a surface as an object moves across it or makes an attempt to move across it
Is frictional force a contact force or non contact
Contact as it force is exerted by the surface when an object moves across a surface or attempts too causing object and surface to be in physical contact
What is tension Force
Force transmitted through a string rope or cable or wire when it is pulled tightly by forces at opposite ends in the opposite direction
Is tension force contact or non contact
Contact force as the string wire or cable needs to be pulled pr stretched in the opposite direction by forces on opposite ends
Spring force
Exerted by any compressed or stretched spring when a object is attached to it
Is spring force contact or non contact
spring force is contact as an object needs to be upon the spring and in contact in order for spring to be stretched or pulled.
What is drag force
It is a special type of frictional force that acts upon objects which move through the fluid
Is drag force contact or non contact
It is a contact force as it takes place only when the object goes through fluid which causes physical contact in order for drag force to occur
What is normal/contact force
Support force exerted upon any object coming into contact with another STABLE object to prevent objects passing through each other
Is normal force a contact or non contact force
Normal force is a contact force as it is a support force exerted upon an object coming into contact with another object to prevent the object passing through
What effect does force have on size or shape of an object
Force applied can change the size or/and shape of an object
What effect does force have on motion
Force applied can change the direction or how an object moves
What is the turning effect
Force applied can change how an object turns about a fixed point or axis
What effect does force have on pressure
Force applied can change the pressure acting across an area
What does effect of forces on motion do?
- Moves stationary object
- Change speed of object
- Change direction of object
- Stop a moving object
What is the definition of the Turning effect
The ability to make something turn
How does turning effect help us
It helps carry out actions requiring the turning or twisting of objects. Example taking lid of a jar
What are the factors affecting urning effect
- Force applied
- Distance of application of force to pivot
How can a larger turning effect be applied
- Applying force at a further distance from pivot [ like holding the wrench at the edge not the mouth ]
- Applying large amount of force
What is pressure? Define it
It is defined as the force acting per unit area
What is the formula of pressure
Pressure = force divide by area of where force is acting
What is SI unit of pressure
Nm^2 OR Pa
Why is a sharp knife easer to cut with
This is because the sharp side of the knife has a very small surface area causing all the pressure to be channeled over there as there is no space to spread, which will be exerted on object being cut, in great amounts due to small surface area making the small area exert a lot of pressure.
Why is blunt knife hard to cut with
Blunt knife has a greater surface area causing pressure to spread out and the pressure exerted by knife to be quite less
Why is it good to hae smaller surface area for pressure
Force is channeled directly to the small area and since it has no place to spread it is exerted out causing force to be great
Why is it bad to have a great surface area for pressure
Pressure is distributed across the object causing force exerted to be lesser
What is the definition of energy
It is the capacity to do work and is required to do work. Enables particles to do work
Energy SI unit
SI unit is Joules [ J ]
Energy examples
- Thermal = heat
- Kinetic = motion
- Potential = chemical [ food ] elastic [ rubber band ] gravitational
- Sound = gas molecules vibrating
- Electrical = movement of electrically charged particles
- Light energy = lets us live
What is the definition of work done?
Work done by a constant force on an object is given by the product of the force and the distance moved by object in direction of force
What is the formula of work done
Work done [ J ] = force [ N ] x Perpendicular distance moved in direction of force [ M ]
How do u know when is work done?
Work is done only when force is applied on the object and it moves.
Object must move in the same direction as applied force
What is the definition of gravitational potential energy
Energy which a body possesses because of its position relative to the ground.
What is gravitational potential energy formula
GPE = mass x gravitational field strength x height
What is the definition of kinetic energy
It is the energy possessed by object due to motion
Kinetic Energy formula
Ke = 1/2 x mass x speed
Does moving body have kinetic energy?
ALL moving body has kinetic energy. When a force moves an object, it does work and the object gains kinetic energy
What is the definition of conversion
Energy cannot be created or destroyed. It can only be transferred or converted, which means total amount of energy remains the same at all times
Example of conversion
If 100J of heat energy is converted to light energy
There will still be 100J light energy. Total amount of energy doesn’t change
What are tsunamis
Force caused by violent movement of ocean floor due to underwater earthquakes or explosions
What do tsunamis cause
Huge waves
Erosion and landslide
Floods
