IPC Chapter 4 Test

The engineering cycle describes how an invention gets from concept to reality.  Which of the following best describes the order of steps in the engineering cycle?

• Evaluate, design, build a prototype test
• Design, build a prototype, test, evaluate
• Design, mass produce, test, and evaluate
• Design, mass produce, apply for a patent, sell stocks

A simple machine often multiplies your

• energy.
• work.
• force.
• power.

Which of the following is NOT considered a simple machine?

• Wheel and axle
• Electric motor
• Lever
• Block and tackle

Mechanical advantage can be defined as the ratio of:

• work input to work output.
• work output to work input
• output force to input force 
• input force to output force

Which of the following block and tackle systems has the largest mechanical advantage?

• System A has the largest mechanical advantage.
• System B has the largest mechanical advantage.
• System C has the largest mechanical advantage.
• All three systems have the same mechanical advantage

A simple machine has an input force of 10 newtons and an output force of 100 newtons.  What is the mechanical advantage of the simple machine?

• 0.1
• 1
• 10
• 90

A simple machine has an input force of 10 newtons and an output force of 100 newtons.  What is the mechanical advantage of the simple machine?

• 0.1
• 1
• 10
• 90

A block and tackle system has an input force of 2.5 newtons and an output force of 10 newtons.  What is the mechanical advantage of the system?

• 0.25
• 4
• 7.5
• 25

On a 10-speed bicycle, gears increase the mechanical advantage of the bicycle.  In which of the following situations would you want the greatest mechanical advantage for the gear system?

• Climbing up an hill
• Coasting down a hill
• Riding on level ground
• Stopping suddenly to avoid a crash

A block and tackle machine is used to lift a box that weighs 90 newtons.  How much force do you need to pull on the rope if the machine has a mechanical advantage of 5?

• 5 newtons
• 9 newtons
• 18 newtons
• 45 newtons