UD: Mechanical Systems Review

Machines cannot

• create energy

• make work easier

• make work faster

• change the direction of the force

What is the fixed point called that a lever pivots around?

• effort arm

• load arm

• fulcrum

• inclined plane

What is the primary fuel type for most traditional lawn mowers?

• gasoline

• electricity

• human power

• natural gas

When multiple simple machines are combined to perform a task, they form a complex machine. What is this combination of machines called?

• A. system

• B. network

• C. innovation

• D. gadget

Linkages and transmissions are parts of a system that perform a specific function. The function they perform is to...

• increase friction

• increase speed

• transfer weight

• transfer energy

Why might the actual mechanical advantage differ from the ideal mechanical advantage in practical applications?

• incorrect measurements

• defective machinery

• frictional forces

• energy loss

A machine that is 85% efficient is basically saying that

• all of the energy put into the machine is wasted

• 15% of the energy put into the device is used

• 15% of the energy put into the device is wasted

• 85% of the energy put into the device is wasted

Consider this picture of a man pushing against rigid brick wall. How much work is the person doing?

• None

• A little

• Enough to make him tired

• A large amount

On the wheelbarrow diagram, what do X, Y and Z represent

• X = the fulcrum, Y = the effort, Z = the load

• X = the fulcrum, Y = the load, Z = the effort

• X = the load, Y = the effort, Z = the fulcrum

• X = the effort, Y = the load, Z = the fulcrum

Which of the following scenarios involves work being done?

• A person leans against a tree

• A car's engine runs while it is parked

• A student lifts her backpack from the floor

• A man tries to lift a heavy box but it doesn't move