Gears

Which gear train would you use to ride up a hill?

• A
• B

What's the ratio?

• 1:1

• 84 : 60

• 60 : 36

When on a bike going uphill, what happens to the speed and torque?

• Speed decreases; torques increases
• Speed decreases; torques decreases
• Speed increases; torques decreases
• Speed increases; torques increases

What is the function of the smaller gear?

• Makes the output gear turn slower
• Makes the output gear turn faster
• Makes the larger gears turn in opposite directions.
• Makes the larger gears turn in the same direction.

A gear ratio is defined as which of the following?

• Teeth of gear : teeth of gear
• gear shape : gear shape
• Speed : torque

What is the formula for calculating gear ratio?

• 
  Driving gear teeth / Driven gear teeth

• 
  Driven gear teeth / Driving gear teeth

• 
  Driving gear teeth - Driven gear teeth

• Driving gear teeth + Driven gear teeth

If a driver gear has 20 teeth and a driven gear has 60 teeth, what is the gear ratio?

• 3

• 5

• 10

• 15

How does a gear ratio affect the speed and torque of a system?

• 
  It only affects the torque, not the speed

• 
  It affects the speed and torque by trading off between the two.

• 
  It only affects the speed, not the torque

• 
  It has no effect on the speed and torque

Explain how gears provide mechanical advantage.

• Gears are only used for decoration and do not provide any mechanical advantage.

• 
  Gears have no effect on the output force or speed.

• 
  Gears decrease the output force or speed compared to the input force or speed.

• 
  Gears increase the output force or speed compared to the input force or speed.

In what ways can gears be used to increase force or speed in a mechanical system?

• 
  By using smaller gears to drive smaller gears for force

• By using larger gears to drive smaller gears for force, and using smaller gears to drive larger gears for speed.

• 
  By using larger gears to drive larger gears for speed

• 
  By using gears of the same size for force