Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Science 8 > Unit 4 > Flashcards

Unit 4 Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

Whats in the middle in a class 1 lever?

A

Fulcrum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Whats in the middle in a class 2 lever?

A

Load

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Whats in the middle in a class 3 lever?

A

Effort

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What advantage does a class 1 lever give?

A

Power

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What advantage does a class 3 lever give?

A

Speed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the unit for work?

A

Joules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

1 Newton is approximately the weight of ____g

A

100

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is an inclined plane?

A

A ramp or slope for reducing the force needed to lift something

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is mechanical advantage?

A

The ratio of force produced by a machine or system (the load) to the force applied to the machine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the formula for MA?

A

Load force/Effort force

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the advantage if MA is over 1?

A

Power

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the advantage if MA is under 1?

A

Speed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the advantage if MA equals 1?

A

Change of direction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is ergonomics?

A

The science of designing home or work environments that best suit human needs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is a winch?

A

A machine consisting of a small cylinder, a crank or handle, and a cable, used for lifting and pulling.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is and example of a winch?

A

Handle of pencil sharpener, Reel of fishing rod

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What MA does a winch give you?

A

Power

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is a wheel and axle?

A

A machine consisting of two turning objects attached to each other at their centers, one object causes the other to turn

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is an example of a wheel and axle?

A

A winch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are some subsystems in a bicycle?

A

Wheel and axle
Gears-Sprocket system
Pedals-Lever
Brakes-lever

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Define gear

A

A rotating wheel like device with teeth around its rims

22
Q

Define gear train

A

A group of two or more gears that are meshed together

23
Q

What is the opposite of a gear train?

A

A sprocket system

24
Q

What is a multiplying gear?

A

When a large gear drives a smaller gear-increases speed and decreases torque

25
Q

What is a reducing gear?

A

When a small gear drives a larger gear-increases torque and decreases speed

26
Q

What is it called when two gears are the same size?

A

Parallel gears

27
Q

What are the four types of pulleys?

A

Fixed-doesn’t move
Movable-moves with the load
Block and tackle-combination of movable and fixed
Compound-one or more pulley together

28
Q

How do you calculate MA of a pulley?

A

Count all the ropes except ones you pull down on

29
Q

Define potential energy

A

Stored energy

30
Q

Define kinetic energy

A

the energy of motion

31
Q

Define transmission

A

Energy is transferred from one place to another and no energy is changed or converted

32
Q

What does it mean to transfer energy?

A

To change the type of energy

33
Q

What is efficiency?

A

The ratio of work energy provided by a machine or system with the actual work or energy supplied to the syetem

34
Q

How can efficiency be boosted?

A
  • Cleaning
  • Lubricating
  • Keep tires inflated
35
Q

What are useful examples of friction?

A

Bike tires against the road
rosin
winter tires
track spikes

36
Q

What is the unit of pressure?

A

Pa (Pascals)

37
Q

What is Pascal’s law?

A

If pressure is applied to a fluid, i will spread out equally in all directions in the shape of the container in a closed system

38
Q

What is a hydraulic system?

A

A device that transmits an applied force through a liquid to move something else by means of pressure.

39
Q

Is hydraulics open or closed?

A

Closed

40
Q

What is a hydraulic system in the human body?

A

The heart

41
Q

What is a pneumatic system?

A

A system in which gas such as air transmits a force exerted on the gas in an enclosed space

42
Q

Is pneumatics open or closed ?

A

Open

43
Q

What is a pneumatic system in the human body?

A

lungs

44
Q

Why are subsystems combined into more complex machines?

A

It makes them more efficient

45
Q

How have machines changed throughout history

A

Machines have become more efficient and work better-ergonomics

46
Q

How does a steam engine work?

A

Water is heated
steam is pressurized
used to make a piston move
the piston is attached to a rod to move engine

47
Q

Why is steam used instead of water?

A

Water would expand and evaporate
too heavy
can’t be compressed

48
Q

What is a piston?

A

A disc shaped part that fits tightly inside a cylinder in which some force, such as steam pressure, moves it back and forth or up and down

49
Q

What is an internal combustion engine?

A

A type of engine in which fuel is burned internally

50
Q

What are the fours strokes of an internal combustion engine?

A

Intake stroke-air is brought in
Compression stroke-fuel is mixed with air and compressed
Power-A spark ignites the fuel
Exhaust-Excess air and fuel go out a valve

Science 8 (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions