Moving and Energy transfer

Question 1

how is energy measured

Answer 1

energy is measured in joules (j) and kilojoules (kj) 1000j = 1kj, it takes 4.2j of energy to heat 1ml of water 1 degree

Question 2

what 2 main types of energy

Answer 2

potential (anything with stored energy, food energy and fuel energy in chemical bonds, gravitational energy in height, nuclear energy stored in the nucleus, and elastic energy stored potential form an object being deformed). kinetic (anything that moves, heat energy particles vibrate, electrical energy electrons move, mechanical energy parts move, electromagnetic waves)

Question 3

what is energy

Answer 3

the ability to do work

Question 4

what is work

Answer 4

energy transfer that occurs when an object is moved over a distance by an external force. the transfer of mechanical energy from one object to another. when no work is being done energy is conserved

Question 5

what is the law of conservation of energy

Answer 5

energy cannot be created or destroyed

Question 6

what is the difference between a transfer and transform of energy

Answer 6

transfer is when energy moves from place to place (e.g heat to body)
transform is when energy changes forms (e.g electrical to light)

Question 7

what are the 3 types of transfer energy

Answer 7

convection (circular motion through fluid)
conduction (objects touching each other)
radiation (through light rays)

Question 8

what happens when water is heated

Answer 8

the particles start to moves due to kinetic energy absorbed by the element

Question 9

what is the difference between heat and temperature

Answer 9

heat is the total amount of heat energy (more hot water=more heat)
temperature is the average heat energy of something

Question 10

what is a circuit

Answer 10

a circuit is a path from one side of a power source (battery) to the other

Question 11

what are the primary keys of a circuit diagrams

Answer 11

file:///C:/Users/rhawkins.13/Pictures/Screenshots/Screenshot%202023-11-06%20224548.png

(put in browser)

Question 12

what is electricity

Answer 12

electricity is the movement of electrons through atoms. if a wire becomes apart of a circuit the electrical field produced by the power sources exerts a force on the electric charge, the atoms don’t move but the electrons do

Question 13

what is current

Answer 13

current is a measure of the number of electrons flowing through a circuit every second, this is measured in amps

Question 14

what is voltage

Answer 14

is the amount of available energy to push thee current of electrons and is supplied by things like batteries. voltage is also used to measure the amount of energy released by an energy user e.g. globe (shit measured in volts V)

Question 15

what is resistance

Answer 15

resistance is something that prevents the flow of electrons (e.g. resistance converts electrical energy into light and heat) (measured in ohms)

Question 16

what is ohms law

Answer 16

is the equations that helps to find out current, resistance, and voltage
V=IR
I=V/R
R=V/I

V=voltage
I=current
R=resistance

Question 17

what is a series circuit

Answer 17

is if you follow the circuit diagram from one cell to the other, you should pass through all the components with no other branches

Question 18

what is a parallel circuit

Answer 18

components are connected via branches of the circuit. unlike the series circuit, if a component breaks then the circuit will keep working

Question 19

what is wasted energy.

Answer 19

When energy is transferred and transformed, e.g. from electric to light in a light bulb, a LOT of energy is transformed into unwanted forms. if an old incandescent bulb needs 100J of energy and produces 10J of energy then it is 10% efficient

Question 20

how to find efficiency of something

Answer 20

output/ input x 100%

Question 21

what is the most efficient renewable energy

Answer 21

wind=62%, hydroelectric=21%
hydro=solar 17%

Question 22

how is electricity generated

Answer 22

When a coil of wire is rotated through a magnetic field the magnets push and pull on electrons. This generates current and is how 90% of our electricity is generated.

All electricity - (except solar) is generated by moving a conductor (wound in a coil) in a magnetic field. Something is burnt to give off heat to boil water and the steam drives the copper coil of wire round and round in a magnetic field. Pushing electrons along wires. Australia burns coal, Europe reacts uranium, New Zealand uses falling water. At Condong, burning sugar cane waste produces ⅓ of Tweed Valley’s electricity.

Question 23

which effect do solar panels use

Answer 23

the photoelectric effect

Question 24

what is inertia

Answer 24

Inertia is the tendency of an object to resist ANY change in motion. All objects have inertia, whether they are moving or not. objects with more mass will have greater inertia. Because of inertia, a resting object will remain at rest. because of inertia, an object will keep moving. To change the motion of an object, inertia must be overcome by a force acting on the object.

Question 25

what are some examples of inertia

Answer 25

When pulling a Band-Aid off, it is better to pull it fast. Your skin will remain at rest due to inertia, and the force pulls the Band-Aid off. If pulled quickly, a tablecloth can be removed from underneath the dishes Seat belts tighten in a car when it stops quickly

Question 26

what is newtons first law

Answer 26

“An object will remain at rest or in uniform notion in a straight line unless acted upon by an unbalanced force” Anything that is moving will keep moving at the same speed and in the same direction unless a force changes it. Inertia explains why you sometimes ‘feel’ lighter or heavier when in a lift as it first moves off or slows to a stop. It also tells why you ‘move sideways’ when a car corners: you keep trying to travel in a straight line.

Question 27

what is an unbalanced force

Answer 27

the force applied in one direction is greater than the force applied in the opposite direction.

Question 28

what is newtons second law

Answer 28

“An object will accelerate if an unbalanced force is applied to it. Its acceleration will depend on the size of the force and the mass of the object”. this law has a formula, force=mass(kg) x acceleration(m/s/s) f=ma m=f/a a=f/m

Question 29

what is newtons third law

Answer 29

“To every action (force) there is an equal and opposite reaction (force)”.

Question 30

what is speed

Answer 30

Speed is the rate at which distance is covered—the amount of distance covered for each unit of time. Commonly used units of time are hours (unit symbol h) and seconds (s). ÷3.6 km/h ⎯⎯→ m/s ←⎯⎯ x3.6

Question 31

what is velocity

Answer 31

Velocity is speed in a given direction. Velocity has the same relationship to speed that displacement has to distance—they are measured in the same units, but add information about direction. average velocity = displacement/ time

Question 32

what is a distance time graph

Answer 32

Distance–time graphs show the total distance travelled by an object as time progresses. Time is always placed on the horizontal axis and distance on the vertical. Steep graphs indicate that the object is covering more distance and travelling faster than flatter graphs.

Question 33

what is a speed time graph

Answer 33

A graph of speed against time gives another picture of what is happening in the motion of an object. As before, time is placed on the horizontal axis. If the object is getting faster, the graph rises. If it is slowing, the graph falls. Constant speed gives a flat graph. The area under a speed–time graph gives the distance that the object has travelled up to that point.

Question 34

how to find gradient of graphs

Answer 34

rise/run

Question 35

what is the speed, distance and time formula

Answer 35

speed=distance x time d=st s=d/t t=d/s