Energy, Work And Power Flashcards Preview

Block Science > Energy, Work And Power > Flashcards

Flashcards in Energy, Work And Power Deck (31):
1

What is work

Force applied over distance

2

What are the units for work

Joules

3

What are the units for energy

Joules

4

What are the units for power

Watts

5

When is no work done

No work is done if no distance is covered in the direction of the force applied

6

In order for work to be done what must be true about force and distance

Force and distance must be in the same direction

7

What is a joule

Newton* meters
Amount of energy needed to apply one Newton of force/ one meters distance

8

Any time work is done what must be used

Energy must be used to do work

9

Define energy

Energy is the ability to do work

10

What are the different categories of energy

Kinetic and potential

11

What is kinetic energy

Kinetic energy is the energy if motion, ex
Sound, light, heat, moving objects, electricity

12

What is potential energy

Potential is the energy of position or stored energy
Ex
Chemical energy, gpe, energy of position, but

13

What is the formula for kinetic energy and what variable matters most

KE= 1/2mV(2)
Most influential is velocity

14

What is the formula for potential energy and what variable is most valuable

GPE= w*h
Height is the most influential

15

What is the law of conservation go energy

Law of conservation of energy states that energy cannot be crated or destroyed only converted from one form to another

16

How does the law of conservation of energy relate to potential and kinetic energy

In the roller coaster lab, PE is converted to KE as the marble rolls down hill, KE is converted to PE as the marble rolls up hill

17

If a roller coaster cars mass is doubled what happens to the amount of kinetic and potential energy that the car will have

Doubling the mass of the car doubles the potential energy at the top and therefore doubles the speed at the bottom

18

If the cars velocity is doubled what will happen to the kinetic and potential energy

Doubling the velocity will mean the car has 4x as much energy

19

As an object falls what happens to the value of potential energy

Potential decreases as an object falls (less hieght=less PE)

20

As an object falls what happens to the value of kinetic energy

KE increases as an object falls because it's velocity is increasing as PE is being converted into KE

21

What is the energy transformation in lighting a match

Chemical energy to heat and light

22

What is the energy transformation in turning in a light

Electrical energy to light

23

What is the energy transformation in starting a car

Chemical energy to kinetic energy of moving energy

24

What is the energy transformation in walking up stairs

Chemical energy to kinetic energy of moving body

25

What is the energy transformation in playing a piano

Chemical energy to kinetic and sound, moving fingers to moving strings into sound

26

What is the formula for work

w=f*d

27

What is the formula for power

P= w/t
P= f*d
--------
T

28

If you have a 50kg object and lift it a distance of 10 meters how much work so you do on the object, how much power of you do it in four seconds?

W= 5,000j
P= 1250watts

29

If you exert 150 joules of energy in 15 seconds, what is your power

P= 10 watts

30

What is the difference between work and power

Work is done when energy is converted from one form to another, power is how fast the energy is converted or how fast the work is done

31

What is gpe

Potential to fall