Chapter 5.1 The Nature of Energy

Question 1

ENERGY

Answer 1

1. Is the capacity to do WORK or

2. The capacity to transfer HEAT

Question 2

WORK

Answer 2

.is the energy used to cause an object to move against force over some distance.
. (w)
. the energy transferred when a force moves an object
. w= f x d ( force ( e.g gravity ) x the distance the object move)

Question 3

HEAT

Answer 3

Is the energy used to cause the temperature of an object to increase.
. It is the energy transferred from a hotter object to a colder one

Question 4

2 Ways that and object can possess energy

Answer 4

1. Kinetic

2. Potential

Question 5

KINETIC ENERGY

Answer 5

the energy of motion

Is the energy an object possesses by virtue of its motion

Question 6

Ek

Answer 6

is the magnitude of kinetic energy Ek=1/2mv2

Question 7

The magnitude of kinetic energy of an object depends on

Answer 7

its mass (m) and speed (v)

Question 8

the magnitude of kinetic energy formula Ek=

Answer 8

Ek =1/2mv^2

Question 9

what happens to kinetic energy of an object as speed and mass increases

Answer 9

Kinetic energy increases. The faster the the object the larger the kinetic energy.
The lager the object the larger the kinetic energy

Question 10

POTENTIAL ENERGY

Answer 10

.An object has potential energy by virtue of its position relative to other objects

.the stored energy that arises from the attractions and repulsions an object experiences in relation to other objects.

Question 11

Instead of forces such as gravity that give rise to potential energy in relation to other objects. What is the force that attracts and repulses atoms and molecules?

Answer 11

Electrical charges

Question 12

The most important form of potential energy when dealing with atoms and molecules

Answer 12

ELECTROSTATIC POTENTIAL ENERGY

Question 13

ELECTROSTATIC POTENTIAL ENERGY

Answer 13

1. E(eb)
2. Arises from the interactions between 2 charged particles.
3. This energy is proportional to
   1. the ELECTRICAL CHARGES on 2 interacting atoms, Q1, and Q2 and
   2. inversely proportional to the DISTANCE, d, separating them

Question 14

THE ZERO OF ELECTROSTATIC POTENTIAL ENERGY

Answer 14

is defined as infinite separation of the charged particles. At infinite separation the magnitude of electrostatic potential energy is zero.

Question 15

LIKE CHARGES AND Eel

Answer 15

REPULSION
.Smaller separation = greater repulsion = higher Eel

. Greater separation = less repulsion=lower Eel

Question 16

OPPOSITE CHARGES AND Eel

Answer 16

ATTRACTION
. Smaller separation = greater attraction=lower Eel
. Greater separation = less attraction= higher ( less negative ) Eel)

Question 17

1J= ? KG

Answer 17

1 kg-m^2/s^2

Question 18

SYSTEM

Answer 18

The portion of the universe that is singled out for study to track the energy changes that occur

Question 19

SURROUNDINGS

Answer 19

All the parts of the universe that is not the system

Question 20

The 3 types of system

Answer 20

1. open
2. closed
3. isolated

Question 21

The SI unit for energy

Answer 21

JOULE

Question 22

1calorie(cal)

. In terms of joules

Answer 22

The amount of energy required to raise the temperature of 1 g of water from 14.5 C to 15.5 C

. 1 cal = 4.184 J

Question 23

A nutritional Calorie

Answer 23

1 Cal = 1000 cal = 1 kcal

Question 24

CLOSED SYSTEM

Answer 24

Systems that can exchange energy but not matter with their surroundings. No mass is lossed or gained from its surroundings. but energy is exchanged in the form of heat and work

Question 25

ISOLATED SYSTEM

Answer 25

where neither energy nor matter can be exchanged with surroundings

Question 26

FORCE

Answer 26

Any push or pull exerted on an object

mass x gravity

Question 27

THERMODYNAMICS

Answer 27

the study of energy and its transformations

Question 28

OPEN SYSTEM

Answer 28

is one in which matter and energy can be exchanged with the surroundings.

e.g.a pot of boiling water on a stove

Question 29

THERMOCHEMISTRY

Answer 29

The portion of thermochemistry a portion of thermodynamics that examine the relationship between chemical reactions and energy changes that involve heat.

Question 30

What happens to potential energy as it is converted into kinetic energy and speed increases

Answer 30

potential energy decreases ( also decreases as a force : repulsion or attraction decrease potential energy decreases)

Question 31

what happens to speed when kinetic energy is converted to potential energy

Answer 31

speed is decreased

Question 32

Heat

Answer 32

Is the energy transferred from a hotter object to a colder one

Question 33

CHEMICAL ENERGY ( e.g. from fuels)

Answer 33

Many substances release chemical energy : energy due the potential energy stored in the bonds of its atoms.

Question 34

A substance THERMAL ENERGY is

Answer 34

is the energy it posses because of its temperature is associated with the KINETIC ENERGY of the molecules in the substance.