P1-Energy Stores and Systems Flashcards Preview

Physics > P1-Energy Stores and Systems > Flashcards

Flashcards in P1-Energy Stores and Systems Deck (21):
1

Name all the energy stores

Thermal
Kinetic
Gravitational Potential
Elastic Potential
Chemical
Magnetic
Electrostatic
Nuclear

2

How is energy transferred?

Mechanically by doing work
Electrically work done by moving charges
Heating
Radiation
Between energy stores

3

What is a system?

A single or group of objects that you are interested in

4

What happens when a system changes?

Energy is transferred into or away from he system, between two objects or between types of energy store

5

What is a closed system?

A system where neither matter nor energy can enter or leave

6

What is the net change in a closed system?

The net change in the total energy of a closed system is always 0

7

Describe the energy transfer of boiling a kettle

Energy is transferred to the water (from kettle heating element) by heating electrically into the waters thermal energy store

8

What is work done?

Work done is another way saying energy transferred. It can be done when current flows or by force moving an object

9

What happens when you throw a ball upward

Initial force is exerted by a person and causes work to be done, energy is transferred from the chemical store in a persons arm to the kinetic energy of the ball and arm

10

What happens when a ball is dropped

The gravity does the work

Causes energy to be transferred from the balls gravitational energy store to its kinetic energy store

11

What happens when a car brakes

Friction between the wheels and the brakes does work as it slows down

It causes energy transfer from the wheels’ kinetic energy stores to the thermal energy store of the surroundings

12

Which store does eventually all energy end up in?

Thermal Store

13

What way can energy use to be transferred

Sound waves

14

If anything is moving what energy store is the energy in?

Kinetic

15

What is the equation for working out kinetic energy

Kinetic Energy (joules)=

1/2 x mass (kg) x speed (m/s) squared

16

If a car of a mass of 2500KG is travelling at 20 m/s calculate the kinetic energy

1/2 x 2500 x 20 x 20

(20 squared)

=500 000 joules

17

When you lift an object work is done, where store does the energy worked go into?

When an object is lifted energy always goes into the gravitational potential energy store

18

What is the equation for the gravitational potential energy

GPE=

Mass x height x gravitational field strength

19

What happens when an object falls

Energy from the gravitational potential energy store is transferred to its kinetic energy store if there’s no air resistance. But if there is then some of the energy will also go into the thermal energy store (like in real life)

20

What store is filled if an object is stretched or squashed

The elastic potential energy store

21

What is the equation for the elastic potential energy store as long as the limit of proportionality has not been exceeded

Elastic potential energy=

1/2 x spring constant (N/m) x extension ^2