Momentum and Energy

Question 1

Momentum and its formula

Answer 1

a vector quantity of motion of a moving body, measured as a product of its mass and velocity. Given by p=mv

Question 2

Conservation of momentum and its formula

Answer 2

States that any interaction or collision between two or more bodies in an isolated system does not change the total momentum. Meaning initial momentum will be equal to final momentum. Given by Pi=Pf

Question 3

Define Impulse and its formula

Answer 3

Impulse is a measure of the change in momentum when two objects interact due to a force acting over time. Given by the formula I=Δp=mΔv

Question 4

What direction will the impulse be?

Answer 4

The direction of an impulse will always be in the same direction as momentum and velocity.

Question 5

Transpose Impulse formula with Newtons second law

Answer 5

Newtons 2nd law is given by F=ma which can be transposed with I=Δp=mΔv and give mΔv=FΔt and simplified to I=FΔt

Question 6

What Ui units can impulse me measured in?

Answer 6

kgm2^-1 or N s

Question 7

collision

Answer 7

the coming together of two or more objects where each object exerts a force on the other

Question 8

impulse

Answer 8

the change in momentum of a body as the result of a force acting over a time (vector quantity)

Question 9

isolated system

Answer 9

A collection of interacting objects for which there is no external exchange of mass and energy

Question 10

energy

Answer 10

a scalar quantity describing the ability to cause a physical change

Question 11

kinetic energy

Answer 11

Kinetic the energy of an object due to its motion

Question 12

power

Answer 12

Power is the rate of change in energy with respect to time

Question 13

work

Answer 13

Work the change in energy caused by a force acting on an object in a direction parallel to its motion

Question 14

Kinetic formula

Answer 14

KE = 1/2mv²

Question 15

Define work as a change in energy and the given formula

Answer 15

Work is a measure of the change in energy caused by a force. If given the energy of an object at two different locations. Given in the formula W = ΔKE

Question 16

Work as the product of a force and displacement formula and what this means on an object

Answer 16

W=FS This means It is equivalent to stating that the kinetic energy of an object can change only when a force is applied parallel to the object’s motion so it either speeds up or slows down.

Question 17

What are three situations where work is done by a constant force:

Answer 17

• If the distance moved is in the same direction as the applied force, energy is transferred to the object. This means the final energy (and speed) is greater than the initial energy (and speed).
• If the distance moved is in the opposite direction to the applied force, energy is transferred from the object. This means final energy (and speed) is less than the initial energy (and speed). The work done will have a negative value.
• If the distance moved is perpendicular to the applied force, no work is done (W = 0).

Question 18

Define kinetic energy of an object and its formula

Answer 18

An object’s kinetic energy is the energy resulting from its motion. Kinetic energy is defined as: KE = ½mv2 where m is the object’s mass and v is its speed. The units of kinetic energy are Joules, just like all other forms of energy.

Question 19

the principle of conservation of energy .

Answer 19

The principle of conservation of energy states that, in the absence of dissipative forces, a system’s total mechanical energy is constant. Dissipative forces such as friction or air resistance will decrease a system’s total mechanical energy

Question 20

Force

Answer 20

The net force that an object is experiencing, is its current acceleration times its mass. Force can also be thought of as the change in momentum per unit time, or mass times the change in velocity per unit time. The SI unit of force is the Newton (N), 1N = 1 kg*m/s2

Question 21

Define energy

Answer 21

energy a scalar quantity describing the ability to cause a physical change

Question 22

Define Kinetic Energy

Answer 22

kinetic energy the energy of an object due to its motion

Question 23

Define Power and its given formula

Answer 23

Power the rate of change in energy with respect to time/ P = ΔE/Δt where P = power (W), E = energy (J), t = time (s).

Power can also be viewed as the rate of work being done (P = W/Δt) when the change in energy is caused by a force.

Question 24

Elastic collision

Answer 24

elastic collision a collision in which kinetic energy is conserved

Question 25

Define energy dissipation

Answer 25

energy dissipation the transfer of energy out of a system

Question 26

Define inelastic collision

Answer 26

inelastic collision a collision in which kinetic energy is not conserved

Question 27

What collision is it when kinetic energy is conserved.

Answer 27

Elastic collisions. This means that the total kinetic energy of the colliding objects before the collision is equal to the total kinetic energy of the objects after the collision.

Question 28

Define gravitational potential energy and its formula

Answer 28

Gravitational potential energy the stored energy associated with the position of an object in a gravitational field. Given formula ΔGPE = mgΔh

Question 29

Conservation of energy

Answer 29

The initial energy equals the final energy of the system. For a system involving only kinetic energy and gravitational potential energy this gives us: KE_i + GPE_i = KE_f + GPE_{f .} Given by the formula:

Question 30

Define compression (spring)

Answer 30

compression (spring) the process of decreasing an object’s length

Question 31

Define extension

Answer 31

extension the process of increasing an object’s length

Question 32

Define an idea spring

Answer 32

An ideal spring a spring that obeys Hooke’s law so that the force it exerts is proportional to its change in length

Question 33

Define natural length in relation to a spring

Answer 33

natural length the length of a spring when no external forces are acting on

Question 34

Define spring constant

Answer 34

spring constant a value that describes the stiffness of a spring

Question 35

Define strain potential energy

Answer 35

strain potential energy the energy stored by the deformation of an object; also known as elastic potential energy or spring potential energy

Question 36

Define Hookes law and its given formula

Answer 36

Hooke’s law describes the linear relationship between the force and displacement of an ideal spring. The spring constant, k, represents the stiffness of spring and determines the amount of force needed to compress or extend a spring. Given formula is F_s = −kΔx

F_s = spring restoring force (N), k = spring constant (N m−1), Δx = displacement from natural position (m)

Question 37

Equilibrium involving springs

Answer 37

For an object attached to a vertical spring, when the force due to gravity acting on the object has the same magnitude as the restoring force of the spring (mg = kΔx), the net force on the object is zero. This is called the equilibrium position.

Question 38

How is strain potential energy calculated?

Answer 38

Question 39

What is strain energy also known as?

Answer 39

Elastic potential energy or spring potential energy.

Question 40

The formula of conversation of energy:

Answer 40

KE_i+GPE_i+SPE_i=KE_f+GPE_f+SPE_f

_{This means: Initial Kinetic energy, gravitational and strain energy equal the final kinetic gravitational and strain energy.}

Question 41

Equilibrium position (spring-mass system)

Answer 41

equilibrium position (spring-mass system) the position of the mass at which the net force on the mass is zero. This position is always halfway between the two extreme points (endpoints) in oscillatory motion

Question 42

Oscillate

Answer 42

move repetitively around a fixed position

Question 43

Spring-mass system

Answer 43

spring-mass system the combination of a spring and a mass that is attached to one end of the spring

Question 44

Energy conservation for a vertical spring-mass system

Answer 44

Question 45

When does the mass come to a stop

Answer 45

At the top and bottom of an oscillation, the mass momentarily comes to a stop

Question 46

Where is the equilbrium position?

Answer 46

– halfway between the top and bottom positions of the oscillating spring.

– where kΔx = mg.

– where a mass will eventually come to rest over time, as energy is dissipated.