Lesson | Unit D_Sci8 - sts 3.1.2.3 | Investigate and describe th

Multiple Choice

What is the primary function of gears in a mechanical system?

• To increase speed

• To increase torque

• To decrease friction

• To change direction.

Multiple Choice

The gear ratio formula uses the number of teeth on the gears. True or False?

• True

• False

Multiple Choice

Fill in the blank: The gear ratio helps determine the ______ advantage.

• Mechanical

• Electrical

• Chemical

• Thermal

Multiple Choice

What does the formula MA = Driven/Driver represent?

• Mechanical Advantage

• Electrical Efficiency

• Chemical Reaction

• Thermal Conductivity

Multiple Choice

In a gear system, which gear applies torque to the other?

• Driven gear

• Driver gear

• Neutral gear

• Reverse gear

Multiple Choice

What is the gear ratio if 10 N of force is applied to the larger gear?

• 14/28

• 10/20

• 5/10

• 7/14

Multiple Choice

If the gear ratio is 14/28 and 10 N of force is applied, what is the output force?

• 10 N

• 5 N

• 20 N

• 15 N

Multiple Choice

Fill in the blank: The formula for mechanical advantage (MA) is MA = ______.

• A) Driver/Driven

• B) Driven/Driver

• C) Force/Distance

• D) Distance/Force

Multiple Choice

What happens to velocity and torque when more force is used to turn the larger gear?

• More velocity, less torque

• More torque, less velocity

• Equal velocity and torque

• No change

Multiple Choice

In the context of gears, what does a higher gear ratio indicate?

• More speed, less force

• More force, less speed

• Equal speed and force

• No effect.

Multiple Choice

What happens to the torque and velocity when a force of 10 N is applied to the smaller gear?

• Torque doubles, velocity halves

• Torque halves, velocity doubles

• Both torque and velocity double

• Both torque and velocity halve

Multiple Choice

Fill in the blank: When a force is applied to the smaller gear, the resulting force from the larger gear is 28/14 x 10 = ___ N.

• 10

• 20

• 30

• 40

Multiple Choice

What is the formula for Mechanical Advantage (MA) in gears?

• MA = Driver/Driven

• MA = Driven/Driver

• MA = Driver x Driven

• MA = Driven + Driver

Multiple Choice

How many teeth does the driver gear have in the diagram?

• 8

• 10

• 18

• 20

Multiple Choice

In the context of gears, what does increasing torque result in?

• Increased speed

• Decreased speed

• No change in speed

• Increased temperature

Fill in the Blanks

What is the gear ratio in the picture on the left if the smaller gear is the driver gear?

Fill in the Blanks

If you apply 100 N of force into the smaller gear, how much force would the larger gear have exerted?

Open Ended

Which is being increased, the velocity or torque? Explain.

Fill in the Blanks

If you apply 100 N of force into the larger gear, how much torque would be created from the smaller gear? (round to the nearest hundredth)

Open Ended

Which is being increased, the torque or the velocity? Explain.

Multiple Choice

What is the mechanical advantage (MA) if the driven gear has 15 teeth and the driver gear has 5 teeth?

• 2

• 3

• 5

• 0.33

Explanation Slide...

The mechanical advantage (MA) is calculated as the ratio of the number of teeth on the driven gear to the driver gear. MA = 15 teeth (driven) / 5 teeth (driver) = 3. Thus, the correct answer is 3.

Multiple Choice

You apply an input force of 100 N to a gear system with a mechanical advantage of 3. What is the output force?

• 100 N

• 200 N

• 300 N

• 400 N

Explanation Slide...

The mechanical advantage (MA) is the ratio of output force to input force. Here, MA = 3, and input force = 100 N. Therefore, output force = MA × input force = 3 × 100 N = 300 N. Thus, the correct answer is 300 N.

Multiple Choice

True or False: A gear ratio less than 1 will increase speed but decrease torque.

• True

• False

Explanation Slide...

A gear ratio less than 1 means the output gear turns faster than the input gear, increasing speed. However, this results in a decrease in torque, as less force is transmitted to the output.

Match

Match the following input forces with their corresponding output forces using a gear system with a mechanical advantage of 0.25.

• 200 N

• 400 N

• 3200 N

• 100 N

Input force of 800 N

Input force of 1600 N

Input force of 12800 N

Input force of 400 N

• Input force of 800 N

• Input force of 1600 N

• Input force of 12800 N

• Input force of 400 N

Explanation Slide...

To find the output force, use the formula: Output Force = Input Force × Mechanical Advantage. Here, Output Force = 800 N × 0.25 = 200 N. Thus, the correct answer is 200 N.

Fill in the Blanks

A driven gear has 8 teeth, and the driver gear has 16 teeth. The gear ratio is

.

Explanation Slide...

The gear ratio is calculated by dividing the number of teeth on the driven gear by the number of teeth on the driver gear. Here, 8 teeth (driven) / 16 teeth (driver) = 0.5. However, the correct answer is 0, indicating a misunderstanding in the question.

Dropdown

In a system with a gear ratio of 3.43,

Select answer

happens.

Explanation Slide...

In a gear system with a ratio of 3.43, torque is increased while speed is decreased. This means that the output torque is greater than the input torque, making the correct choice 'Torque is increased'.

Multiple Choice

An input force of 1200 N is applied to a system with a mechanical advantage of 3.43. What is the output force?

• 1200 N

• 4000 N

• 4116 N

• 3430 N

Explanation Slide...

To find the output force, multiply the input force by the mechanical advantage: 1200 N * 3.43 = 4116 N. Thus, the correct output force is 4116 N.

Multiple Choice

True or False: If the driven gear has more teeth than the driver gear, torque increases.

• False
• True

Explanation Slide...

When the driven gear has more teeth than the driver gear, it increases the mechanical advantage, resulting in higher torque output. This is due to the gear ratio favoring torque over speed.

Multiple Choice

An input force of 1750 N is applied to a system with a gear ratio of 2. What is the output force?

• 3500 N

• 875 N

• 4000 N

• 1500 N

Explanation Slide...

The output force can be calculated using the gear ratio. With a gear ratio of 2, the output force is 1750 N (input) x 2 = 3500 N. Therefore, the correct answer is 3500 N.

Fill in the Blanks

In a gear system with a driver gear of 40 teeth and a driven gear of 48 teeth, the gear ratio is

.

Explanation Slide...

The gear ratio is calculated as the number of teeth on the driven gear divided by the number of teeth on the driver gear. Here, it is 48/40 = 1.2, not 0.83. Therefore, the correct answer is 0.

Multiple Choice

Which of the following statements best explains why a gear system with a ratio less than 1 increases speed but reduces torque?

• The driver gear is larger, transferring energy faster but with less force

• The driver gear is smaller, causing the driven gear to spin faster

• Energy is lost in the system

• The teeth on the gears are not aligned

Explanation Slide...

The correct choice explains that the driver gear is larger, which allows it to transfer energy faster to the driven gear. This results in increased speed but reduced torque, as the larger gear applies less force.

Drag and Drop

A student designs a machine that uses a 5-tooth driver gear and a 15-tooth driven gear. They apply 1500 N of force. The output force will be

Placeholder

Drag these tiles and drop them in the correct blank above

500 N

1500 N

3000 N

4500 N

Explanation Slide...

The gear ratio is 15:5, or 3:1. This means the output force is 3 times the input force. Therefore, 1500 N x 3 = 4500 N, making the correct answer 4500 N.