P h y s Flashcards
What is the calculation of density, mass and volume?
Density: mass/volume
Mass: density x volume
Volume: mass/density
When does pressure occur?
Pressure occurs when force acts on area
Pressure: force/area
Force: pressure x area
What s the calculation for the moment of force?
Moment of force: force x distance of pivot
What device is used to measure if an object has a negative or positive charge?
Coulombmeter
What are fossil fuels?
Stores of chemical energy, e.g coal, oil, natural gas
How many types of energy are there and what are they?
- 2 main types of energy
- potential energy (PE) and kinetic energy (KE)
Name 8 types of energy
Gravitational potential energy (PE) Strain energy (PE) Chemical energy (PE) Kinetic energy of moving bodies (KE) Sound energy (KE) Electrical energy (KE) Internal energy (KE) Electromagnetic energy (KE)
What device do you use to measure the current and voltage and what is their unit?
Current: device used is ammeter; unit is amp
Voltage: device used is voltmeter; unit is volt
What is the law of reflection?
Angle of reflection = angle of incidence
What is refraction
Refraction: when light changes its direction
Name the colors in the rainbow:
Red Orange Yellow Green Blue Indigo Violet
What is friction?
Friction: contact force occurring between 2 surfaces when a push or pull could cause 1 surface to move over the other.
*Static friction: small pushing/pulling force is generated to slide one surface over another.
Sliding friction: if pushing/pulling force is further increased, one surface will slide over the other.
What is increasing and reducing friction?
Increasing friction: pressing surfaces makes projections and hollows lock together
Reducing friction: a liquid applied to 2 surfaces fills the hollows and makes contact between surface smoother.
What is air resistance?
Air resistance: when an object moves through air, the objects pushes on air and air pushes back with force.
What’s the difference between mass and weight?
Mass: the amount of matter in it; measured in g and kg
Weight: the pull of earth’s gravity on the object; measured in newtons (N)
*1kg = 10N
*planets with larger mass will have larger gravitational field strength.
What is speed and how do you measure speed?
Speed: measure of distance covered by a moving object in a certain time
Speed = distance/time
How do you find the density of. A. Liquid?
1- find mass of cylinder, M1. 2- Pour certain volume into measuring cylinder, V. 3- Find mass of liquid and cylinder, M2. 4- Find mass of liquid, M2-M1 = M1 5- Find density, M1/V
How many types of energy resources are there and what are they?
- 2 types of energy resources
- Renewable energy (RE) and non-renewable energy (NRE)
Give 8 types of energy resources:
Fossil fuels (NRE) Radioactive elements (NRE) Hydro electric (RE) Wind (RE) solar (RE) Fuel wood (RE) Geothermal (RE) Waves (RE)
How are the 3 ways that heat or thermal energy move?
Conduction: occurs easily in solids
convection: occurs in liquids/fluids and gasses
Radiation: occurs in space or gas’
Evaporation: particles in liquid have different amount of energy; the higher the. Energy, the faster they move
Why are we able to see the moon?
We can see the moon because it reflects the sun’s light; it’s non luminous
What is the device you use to measure sound waves?
Oscilloscope
What is frequency and amplitude and how do you measure it.
Frequency: the pitch of a sound; measured in Hz
Amplitude: loudness of a sound
What is the law of the conservation of energy?
Law of the conversation of energy states that energy cannot be made or destroyed, it can only be changed from one form to another.
How do you know if a sound has a soft amplitude or loud amplitude
Soft sound: sound waves are low
Loud sound: sound waves are high
How do you know if a sound has a high pitch or low?
High pitch: a lot of sound waves
Low pitch: sound waves are spread out
What are the primary and secondary colours?
Primary: red, blue, green
Secondary: cyan, magenta, yellow
What is a magnetic material and domains?
Magnetic material: one that’s attracted to a magnet and can be made into a magnet.
Domains: inside magnetic material; many tiny regions that behave like microscopic magnets.
When do magnets repel and attract?
Similar poles repel and different poles attract.
E.g. north pole repels north pole
North pole attracts south pole
What’s a magnetic field?
Magnetic field: the region around a magnet where pull of magnetic force acts on magnetic material.
What is an electromagnet and how does it work?
Electromagnet: made by wrapping wire around iron bar so wire makes a coil.
-when electric current passes through coil, magnetic field from coil turns iron bar into magnet (that can be used to lift things up).
If 2 balloons were negatively charged and are brought close together, will it repel or attract?
It will repel just like electrical charges
What is an induced charge?
- an induced charge is one that is made in a material by a charged material without 2 materials touching.
What”s a series circuit and a parallel circuit?
Series: all components are in line.
Parallel: components are arranged side by side.
Which direction does the sun come up and go down from?
- The earth rotates on an axis and the earth rotates once on its axis in a day.
- The sun comes from the east and goes down on the west.
