8D: Mechanical Systems

Question 1

<p>what is an inclined plane used for?</p>

Answer 1

<p>a inclined plane is used for lifting heavy objects up and down.</p>

Question 2

<p>what is a wedge used for?</p>

Answer 2

<p>a wedge is used for pushing objects apart.</p>

Question 3

<p>what is a pulley used for?</p>

Answer 3

<p>a pulley is used for pulling heavy objects up and down.</p>

Question 4

<p>what is a wheel and axle for?</p>

Answer 4

<p>a wheel and axle is a simple machine that helps us because if you want to open a door then a door knob is a wheel and axle .</p>

Question 5

<p>what makes a lever go up and down?</p>

Answer 5

<p>what makes levers go up and down like a teeter totter is an object in the middle of the lever then who ever stands or touches it the lever goes one way and then the other way.</p>

Question 6

<p>why wegdes split objects in half?</p>

Answer 6

<p>as you force the wedge down it pushes sideways to split an object.</p>

Question 7

<p>is a nut cracker a simple machine?</p>

Answer 7

<p>yes a nut cracker is a simple machine a nut cracker is a lever it breaks the nut open.</p>

Question 8

<p>are mill wheels simple machines?(waterwheel)</p>

Answer 8

<p>yes a mill wheel is a simple machine its a wheel and axle.</p>

Question 9

<p>how many simple machines are there?</p>

Answer 9

<p>there are 6 different simple machines that help us at our work.</p>

Question 10

What is input force?

Answer 10

force applied to perform work

Question 11

Simple machine

Answer 11

a tool or device made up of one basic machine

Question 12

Output force

Answer 12

what a machine does in return for input

Question 13

What is meant by the term efficiency? (With regards to mechanical systems)

Answer 13

Efficiency is the measurement of how effectively a machine uses energy. It is directly correlated to mechanical advantage and speed ratio.

Question 14

What type of simple machine is a pair of scissors?

Answer 14

Scissors are classified as levers because of the way the move when cutting.

Question 15

Using the formula MA = output force/input force, what is the mechanical advantage of pulley with an input of 45 N and an output of 180 N?

Answer 15

The mechanical advantage is 4: 180/45 = 4

Question 16

A screws shape has an inclined plane. True or false?

Answer 16

True: the spiral grooves in a screw are considered inclined planes.

Question 17

Efficiency explains how fast/slow an object moves across a certain distance. True or false.

Answer 17

False. Efficiency is a measurement of how well a machine/device uses energy. Speed ratio, on the other hand, explains how fast/slow an object moves across a certain distance.

Question 18

Is it good to have a machine with a mechanical advantage of 1?

Answer 18

No, it is not good to have a machine with a mechanical advantage of 1 because it doesn’t make your work any easier. It just means you are doing the same amount of work if you didn’t use the machine.

Question 19

What is the difference between a complex machine and a simple machine?

Answer 19

A simple machine is one machine that makes work easier, while a complex machine is is made of multiple devices.

Question 20

A pulley has a mechanical advantage of 3 and an input of 88 N. What is the pulleys output?

Answer 20

The output of the machine is 264 N.

Question 21

Mike was playing on the playground and he saw many machines like slides and seesaws. What type of simple machines did Mike see?

Answer 21

A slide is an example of an inclined plane. Twirly slides can also be considered screws. A seesaw is one of the most basic examples of a lever.

Question 22

Bob is trying to move a large rock into his van, (don’t ask why, he’ll just get mad). He is not sure if he should lift it on his own. Would it be more efficient to lift it himself or use an inclined plane?

Answer 22

It would be much more efficient to use an inclined plane to get the rock into the van because it will lighter the amount of work Bob has to exert.

Question 23

A knife is not considered a wedge because it is smooth. True or false?

Answer 23

False. A knife is a wedge because it has a small edge and is used to seperate objects using force.

Question 24

What common unit of transportation, had a mechanical advantage less than 1, but is still useful?

Answer 24

A bike has a mechanical advantage less than 1 because it has a large input force and a small output force.

Question 25

Why can friction be a negative force when moving objects?

Answer 25

Friction can be a negative force bcuse it opposes motion. This means that is slowly the object you are moving and makes it harder for you to finish your task.

Question 26

Bicycles, pencil sharpeners and door handles are all examples of: A) simple machines b) complex machines c) mechanical work devices

Answer 26

The correct answer is b) complex machines. This is because they are made of multiple simple machines.

Question 27

Why may a machine have a mechanical advantage lower than 1?

Answer 27

A machine may have a mechanical advantage lower than one because it does not make your work easier. It makes it much harder.

Question 28

Using the formula work = distance x force, solve the following equation: Bob moved a camera 1.5 m using 20 N. What is the work of his task?

Answer 28

This task took 30 joules of work.

Question 29

What are the simple machines?

Answer 29

Lever, Pulley, Wheel and Axle, Screw, Inclined plane, and Wedge.

Question 30

What two simple machines are in a hole puncher?

Answer 30

In a hole puncher there is a wedge and a lever.

Question 31

What is a Lever and what is it used for?

Answer 31

A stiff, solid bar sitting atop a resting point. It is used for moving heavy loads.

Question 32

What is a Pulley and what is it used for?

Answer 32

A wheel with a rim around it on each side which a rope passes through. It is used to lift heavy objects.

Question 33

What is a Wedge and what is it used for?

Answer 33

A triangle made of a rigid material. You can drive it in between two objects to secure or split the object.

Question 34

What is a Wheel and Axle and what is it used for?

Answer 34

It is a wheel with a cylindrical tube going through the center. Also able to lift heavy objects with it.

Question 35

What is a Screw and what is it used for?

Answer 35

It is a thin cylinder with a sharp end. An inclined plane wraps around the tube. Used to hold two objects together.

Question 36

What is an Inclined Plane and what is it used for?

Answer 36

An inclined plane is a rigid board that is leaned on another object to make an incline. You can use it to push an object up or down.

Question 37

How do you calculate Mechanical Advantage?

Answer 37

You divide your output force by your input force. Output over Input.

Question 38

What are two examples of a complex machine?

Answer 38

Bycicle, Hole puncher, Stapler, Scissors, etc…

Question 39

What is the point that the lever balances on called ?

Answer 39

The fulcrum

Question 40

What is the purpose of a wedge ?

Answer 40

The purpose is to split objects into peices

Question 41

What one of theses are a wedge ? a) screw b) axe c) domino d) all above

Answer 41

b) axe

Question 42

How many kinds of pulley(s) are there and what are is the name(s) of it? a) 1 b) 2 c)3

Answer 42

b) 2 a fixed and movable

Question 43

What is the difference of a movable and fixed pulley ?

Answer 43

Fixed can’t move what you use for a wheel+ axle and movable can move what you use as a wheel+ axle