Machines

$\text{Load} / \text{Effort}$

$\text{Effort} / \text{Load}$

$\text{Force} \times \text{Distance}$

$\text{Work} / \text{Time}$

$100\text{ J}$

$1\text{ J}$

$0\text{ J}$

$1000\text{ J}$

$0$

$1$

$2$

$0.5$

Simple machine

Wedge

Compound machine

First-class lever

3.2

4

5

20

Smaller

Higher

Equal

Zero

Work is done when a person holds a heavy box still

Work is done when a force causes an object to move in the direction of the force

Work is a measure of how fast an object moves

Work depends only on the mass of the object

$100\text{ N}$

$2500\text{ N}$

$125\text{ N}$

$500\text{ N}$

$400\text{ RPM}$

$25\text{ RPM}$

$50\text{ RPM}$

$100\text{ RPM}$

To increase the Velocity Ratio.

To increase the Mechanical Advantage.

To decrease the effort distance.

To increase the efficiency of the cutting process.

$Speed = Distance / Time$

$Speed = Force \times Distance$

$Speed = Mass \times Acceleration$

$Speed = Work / Time$

Screw

Wedge

Pulley

Wheel and Axle

Move the fulcrum closer to the load

Move the fulcrum closer to the effort

Decrease the length of the lever

Increase the weight of the load

They are the same thing

Work is the transfer of energy

Work is force, energy is mass

There is no relationship

To increase force

To save energy

To increase speed or distance

To eliminate friction

Clockwise

Counter-clockwise

It will not turn

Up and down

$20\%$

$80\%$

$120\%$

$50\%$

The velocity ratio must be equal to $1$.

There must be no friction or moving parts with mass.

The effort must be equal to the load.

The machine must be a first-class lever.

$10,000\text{ W}$

$1,000\text{ W}$

$5,000\text{ W}$

$20,000\text{ W}$

Double second-class lever

Double first-class lever

Single third-class lever

Wedge and pulley combination

$2\ J$

$15\ J$

$50\ J$

$500\ J$

Move the fulcrum closer to the load

Move the fulcrum further from the load

Increase the weight of the lever

Apply less force

First

Second

Third

Fourth

Load

Fulcrum

Effort

Resistance

The ratio of output force to input force

The ratio of distance moved by effort to distance moved by load

The ratio of work out to work in

The ratio of power to time

The first person

The second person

They have the same power

Power cannot be determined

The force applied to the machine

The weight or resistance the machine overcomes

The pivot point of the machine

The time taken to do the work

$60\%$

$83\%$

$12\%$

$50\%$

$3.0$

$4.0$

$0.75$

$1.33$

$-60\text{ J}$

$60\text{ J}$

$6\text{ J}$

$-6\text{ J}$

20

5

12

8

Do more work in a shorter amount of time

Do work for a longer time

Store more energy

Create energy

Gravity

Friction

Magnetism

Speed

Energy that is lost to the air

Energy used for the intended purpose of the machine

The total energy provided by the battery

Energy produced by friction

200 J

5000 J

1005 J

0.005 J

Newton-meter (N·m)

Watt per second (W/s)

Kilogram (kg)

Newton per meter (N/m)

0.2

5

400

600

$100\text{ J}$

$75\text{ J}$

$1200\text{ J}$

$400\text{ J}$

$2$

$5$

$0.5$

$2.5$

$0.2$

$5$

$80$

$24$

The total energy used

The rate at which work is done

The strength of the materials

The size of the machine

A pulley

A battery

A plastic casing

A sensor

The force the machine applies to the object

The force applied to the machine by the user or motor

The weight of the machine

The force of friction inside the machine

By adding more wheels

By forcing more air into the combustion chamber

By making the car change color

By removing the need for fuel

The price of the robot

The number of independent ways in which a dynamic system can move

The amount of storage in the robot's memory

The battery life of the robot

To pay the taxes for the machine

To automatically control and maintain the speed of the machine

To provide the initial spark for combustion

To clean the exhaust gases

It can only be used for very high speeds

The gear can easily drive the worm backwards

It allows for a high gear reduction in a small space and usually locks in one direction

It is the most efficient gear system known

Pneumatics can provide much higher forces for heavy lifting.

Hydraulic fluids might freeze or leak in the extreme Martian cold and low pressure.

Pneumatics are much heavier and would help the rover stay on the ground.

Hydraulics are too fast for the slow-moving rover.

Increased biodiversity due to machine-made habitats.

Reduction in global energy demand because machines are efficient.

Depletion of rare-earth minerals and increased carbon emissions.

Total elimination of the greenhouse effect.

The addition of forces in a parallel system.

The multiplication of mechanical advantages in a compound machine.

The subtraction of friction from the total work input.

The conversion of potential energy into kinetic energy.

Option A

Option B

Option C

Option D

$(Work Input \div Work Output) \times 100\%$

$(Work Output \div Work Input) \times 100\%$

$Work Output + Work Input$

$Force \times Distance$

A screwdriver

A pair of tongs

A bottle cap

A wood axe

Shorter

Longer

Equal

Vertical

By increasing the time needed for basic survival tasks

By increasing productivity and making goods more affordable

By making all human skills obsolete

By decreasing the amount of energy available

It uses only one simple machine

It is operated manually by one person

It combines many simple machines and energy systems to perform tasks

It has $100\%$ efficiency

Inclined Plane

Screw

Pulley

Wedge

$25$

$100$

$4$

$15$

It is sent to a landfill to decompose.

It is incinerated to produce energy.

It is designed to be disassembled so that its components and materials can be reused or recycled.

It is stored indefinitely in a warehouse.

Because the load is supported by two segments of the rope, each moving half the distance the effort moves.

Because the radius of the pulley is always half the diameter.

Because friction always halves the distance moved.

Because the pulley rotates twice for every one meter of rope pulled.