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Physics Foundations: Q&A Review

Use this document to test your understanding of Tutorials 1.1-1.3

Complete all sections, then check your answers at the end. Aim for 80% or better before moving on!

Section 1: True or False (15 Questions)

Write T (True) or F (False) for each statement.

Forces and Motion

  1. ___ An object at rest will stay at rest forever unless a force acts on it.
  2. ___ A heavier robot needs more force to accelerate at the same rate as a lighter robot.
  3. ___ Momentum only depends on how fast an object is moving.
  4. ___ If you double the force on a robot, its acceleration doubles (assuming mass stays the same).
  5. ___ A light robot is always better than a heavy robot in competition.

Gears and Torque

  1. ___ The BLUE (6:1) gear cartridge provides the most torque.
  2. ___ A higher gear ratio means more speed but less torque.
  3. ___ The GREEN (18:1) cartridge is a good choice for drivetrains because it balances speed and torque.
  4. ___ If you change the gear cartridge in code, you don't need to change it physically in the motor.
  5. ___ Bigger wheels cover more distance per rotation but need more torque to accelerate.

Friction and Traction

  1. ___ Static friction is weaker than kinetic (moving) friction.
  2. ___ Omni wheels have rollers that allow them to slide sideways.
  3. ___ Traction wheels are the best choice for easy turning.
  4. ___ Keeping the center of gravity low makes a robot more stable.
  5. ___ A wider track width makes a robot turn faster.

Section 2: Multiple Choice (20 Questions)

Circle the best answer for each question.

Forces and Motion

1. Newton's First Law says that objects: - A) Always accelerate when force is applied - B) Stay at rest or keep moving unless acted on by a force - C) Move faster when they're heavier - D) Stop immediately when force is removed

2. A robot weighs 10 kg and accelerates at 2 m/s². What force do the motors provide? - A) 5 Newtons - B) 12 Newtons - C) 20 Newtons - D) 8 Newtons

3. Which has MORE momentum: a 5 kg robot at 4 m/s OR a 10 kg robot at 2 m/s? - A) The 5 kg robot - B) The 10 kg robot - C) They have equal momentum - D) Cannot determine without more information

4. In Push Back, why might you want a heavier robot? - A) It's faster - B) It's harder to push around - C) It uses less battery - D) It turns more easily

5. The clamp() function in code is used to: - A) Connect motors together - B) Limit values between a minimum and maximum - C) Calculate momentum - D) Measure friction

6. When you push an opponent robot, they push back on you. This is: - A) Newton's First Law - B) Newton's Second Law - C) Newton's Third Law - D) The Law of Friction

7. If you want a robot to accelerate faster, you should: - A) Add more weight - B) Reduce motor power - C) Increase motor force - D) Use smaller wheels

Gears and Torque

8. Torque is best described as: - A) Speed of rotation - B) Twisting or rotational force - C) Distance traveled per minute - D) The weight of a gear

9. Which VEX V5 cartridge should you use for a flywheel that needs to spin very fast? - A) RED (36:1) - B) GREEN (18:1) - C) BLUE (6:1) - D) Any cartridge works the same

10. What does a 36:1 gear ratio mean? - A) The motor spins 36 times for every 1 output rotation - B) The output is 36 times faster than the motor - C) The motor provides 36 Newtons of force - D) The wheel is 36 inches in diameter

11. If the GREEN cartridge gives 200 RPM, what does the RED cartridge give? - A) 600 RPM - B) 400 RPM - C) 100 RPM - D) 50 RPM

12. You need to lift a heavy arm. Which cartridge provides the most torque? - A) BLUE (6:1) - B) GREEN (18:1) - C) RED (36:1) - D) They all provide the same torque

13. Your robot uses 4-inch wheels with GREEN cartridges (200 RPM). What is the wheel circumference? - A) About 100 mm - B) About 200 mm - C) About 319 mm - D) About 400 mm

14. If you switch from GREEN (18:1) to BLUE (6:1) cartridges, your robot will: - A) Be slower with more pushing power - B) Be faster with less pushing power - C) Have the same speed and power - D) Use less battery

Friction and Traction

15. Why do omni wheels make turning easier? - A) They're lighter - B) They have rollers that slide sideways - C) They spin faster - D) They have more friction

16. Which wheel type provides the MOST friction/grip? - A) Omni wheels - B) Traction wheels - C) Mecanum wheels - D) All wheels have equal friction

17. Static friction helps your robot because: - A) It makes the robot slide easier - B) Wheels grip the floor before the robot moves - C) It reduces battery usage - D) It makes turns faster

18. A robot with a HIGH center of gravity is: - A) More stable - B) Less likely to tip - C) More likely to tip - D) Faster

19. In Push Back, a defensive robot should probably use: - A) All omni wheels for speed - B) Traction wheels for grip - C) Mecanum wheels for strafing - D) No wheels

20. What happens when wheels spin faster than they can grip the floor? - A) The robot accelerates faster - B) The wheels "burn out" and the robot doesn't move efficiently - C) The robot stops immediately - D) Friction increases

Section 3: Fill in the Blank (10 Questions)

Complete each statement with the correct word or value.

  1. Force = _ × Acceleration

  2. Momentum = Mass × _

  3. The BLUE gear cartridge spins at _ RPM.

  4. The GREEN gear cartridge has a ratio of _:1.

  5. Higher gear ratios provide more _ but less speed.

  6. _ friction is the force that prevents objects from sliding when they're not moving yet.

  7. _ wheels have small rollers around their edges.

  8. The center of _ is the balance point of a robot.

  9. Your robot's track width is the distance between the _ and _ wheels.

  10. When wheels spin but the robot doesn't move, there's not enough _.

Section 4: Calculation Problems (10 Questions)

Show your work for each problem.

Force Calculations

1. Robot A weighs 6 kg. What force is needed to accelerate it at 3 m/s²? 

F = m × a
F = ___ × ___
F = ___ Newtons

2. Robot B weighs 12 kg and its motors provide 24 Newtons of force. What is its acceleration? 

a = F ÷ m
a = ___ ÷ ___
a = ___ m/s²

3. You want Robot C (8 kg) to accelerate at 4 m/s². What force is needed? 

F = ___ × ___
F = ___ Newtons

Momentum Calculations

4. Calculate the momentum of a 7 kg robot moving at 3 m/s. 

p = m × v
p = ___ × ___
p = ___ kg·m/s

5. Robot X (4 kg, 5 m/s) vs Robot Y (10 kg, 2 m/s). Which has more momentum? 

Robot X: p = ___ × ___ = ___ kg·m/s
Robot Y: p = ___ × ___ = ___ kg·m/s
Winner: Robot ___

Gear Calculations

6. A motor provides 2 N·m of torque through a RED (36:1) cartridge. What is the output torque? 

Output Torque = Input Torque × Gear Ratio
Output Torque = ___ × ___
Output Torque = ___ N·m

7. With BLUE cartridges (600 RPM) and 4" wheels (319 mm circumference), how far does the robot travel in 1 minute? 

Distance = RPM × Circumference
Distance = ___ × ___ mm
Distance = ___ mm = ___ meters

8. If you have a 60-tooth wheel gear and a 12-tooth motor gear, what is the external gear ratio? 

Ratio = ___ ÷ ___
Ratio = ___:1

Speed Calculations

9. Robot with GREEN cartridge (200 RPM), 4" wheels (319 mm). What is the speed in m/s? 

Distance per minute = 200 × 319 mm = ___ mm
Speed = ___ mm ÷ 60 seconds = ___ mm/s
Speed = ___ m/s

10. If you switch to RED cartridges (100 RPM) with the same wheels, what's the new speed? 

Speed = (100 × 319) ÷ 60 = ___ mm/s = ___ m/s

Section 5: Scenario-Based Questions (8 Questions)

Choose the best solution for each competition scenario.

1. Your robot keeps getting pushed backward by opponents. What could you change? (Select all that apply) - [ ] A) Switch from omni to traction wheels - [ ] B) Add weight to the robot - [ ] C) Use RED cartridges instead of GREEN - [ ] D) Use BLUE cartridges instead of GREEN

2. Your drivetrain is too slow but you have plenty of pushing power. What should you change? - A) Switch to RED (36:1) cartridges - B) Switch to BLUE (6:1) cartridges - C) Add more weight - D) Use smaller wheels

3. Your robot tips over when turning quickly. What's the best fix? - A) Move the battery higher - B) Move heavy components lower - C) Use a narrower wheel base - D) Increase motor speed

4. You need an intake mechanism that spins rollers very fast to grab blocks. Which cartridge? - A) RED (36:1) for maximum grip - B) GREEN (18:1) for balance - C) BLUE (6:1) for speed - D) It doesn't matter

5. Your autonomous routine needs to turn exactly 90 degrees, but the robot overshoots. What's likely the problem? - A) Not enough friction - B) Too much momentum carrying the robot past the target - C) The battery is low - D) The gear ratio is wrong

6. During a match, your wheels are spinning but the robot isn't moving well on a dusty floor. Why? - A) Too much static friction - B) Not enough friction between wheels and floor - C) The motors are too powerful - D) The gear ratio is too high

7. You're building a defensive robot that needs to block opponents. Prioritize these features (1=most important): - ___ Maximum speed - ___ Maximum pushing power (torque) - ___ Easy turning - ___ Stability (low center of gravity)

8. Your alliance partner has a fast scoring robot. What should YOUR robot focus on? - A) Also being fast at scoring - B) Defense and blocking opponents - C) Having the exact same design - D) Using all omni wheels

Section 6: Match the Terms (15 Pairs)

Draw lines or write the matching letter.

Set A: Concepts and Definitions

Term Definition
1. Torque A. Resistance between surfaces
2. Friction B. Balance point of an object
3. Momentum C. Rotational force
4. Acceleration D. How much the motor is geared down
5. Gear Ratio E. Mass × Velocity
6. Center of Gravity F. Change in velocity over time

Set B: Analogies and Physics Concepts

Analogy Concept
7. Bicycle gears G. Newton's Third Law
8. Running on ice vs grass H. Gear ratios (torque vs speed)
9. Shopping cart (empty vs full) I. Friction
10. Push opponent, they push back J. Mass affects acceleration

Set C: Wheel Types and Use Cases

Wheel Type Best Use
11. Traction wheels K. Smooth turning on tank drive
12. Omni wheels L. Maximum grip for pushing
13. Mecanum wheels M. Moving in any direction

Set D: Cartridges and Applications

Cartridge Best Application
14. BLUE (6:1) N. Drivetrain (balanced)
15. RED (36:1) O. Flywheel/intake (speed)
16. GREEN (18:1) P. Lift arm (strength)

Section 7: Diagram Labeling (3 Diagrams)

Diagram 1: Forces on a Moving Robot

Label the forces A, B, C, D on this diagram:

                    [C]
                     ↓
              +--------+
         [A]← |  ROBOT | →[B]
              +--[O][O]+
                  ↑
                 [D]
              ═══════════

Options: Friction, Motor Force (forward), Gravity, Normal Force (floor pushing up)

A = ___ B = __ C = _ D = ____

Diagram 2: Gear Ratio Identification

Which setup gives MORE TORQUE at the output?

Setup 1:                    Setup 2:

  [Small]──[Large]            [Large]──[Small]
  Motor    Output             Motor    Output
     12     36 teeth             36      12 teeth

Answer: Setup ___ gives more torque because ___

Diagram 3: Wheel Type Identification

Identify each wheel type:

   Type A              Type B              Type C

   +====+              +----+              +----+
   |████|              | ⟋⟋ |              | ╲╲ |
   |████|              | ⟋⟋ |              | ╲╲ |
   +====+              +----+              +----+

   Rubber tread        Side rollers        Angled rollers

A = ___ B = __ C = ____

Answer Key

Section 1: True or False

  1. T - Newton's First Law (objects at rest stay at rest)
  2. T - F = ma, so more mass needs more force for same acceleration
  3. F - Momentum = mass × velocity (depends on both)
  4. T - F = ma, double F means double a (if m is constant)
  5. F - Trade-off: heavy = harder to push, light = faster but easier to push
  6. F - BLUE has the LEAST torque (more speed)
  7. F - OPPOSITE! Higher ratio = more torque, less speed
  8. T - GREEN (18:1) is balanced, commonly used for drivetrains
  9. F - You MUST change both code AND physical cartridge
  10. T - Bigger wheels = more distance, but need more force to accelerate
  11. F - Static friction is STRONGER than kinetic
  12. T - That's exactly what the rollers do
  13. F - Traction wheels make turning HARDER (scrubbing)
  14. T - Low center of gravity = more stable
  15. F - Wider track width = slower turns, but more stable

Section 2: Multiple Choice

  1. B - Objects stay at rest or keep moving unless acted on
  2. C - F = 10 × 2 = 20 Newtons
  3. C - Both = 20 kg·m/s (5×4 = 20, 10×2 = 20)
  4. B - Harder to push around (Newton's Laws)
  5. B - Limits values between min and max
  6. C - Newton's Third Law (action/reaction)
  7. C - More force = more acceleration (F = ma)
  8. B - Torque is twisting/rotational force
  9. C - BLUE (6:1) = highest speed
  10. A - Motor spins 36 times per 1 output rotation
  11. C - RED = 100 RPM (half of GREEN's 200 RPM)
  12. C - RED (36:1) provides the most torque
  13. C - 4 × π × 25.4 ≈ 319 mm
  14. B - BLUE = faster but less pushing power
  15. B - Rollers allow sideways sliding
  16. B - Traction wheels have rubber tread
  17. B - Wheels grip before moving
  18. C - High CG = more likely to tip
  19. B - Traction for maximum grip
  20. B - "Burn out" - wheels spin without moving robot

Section 3: Fill in the Blank

  1. Mass
  2. Velocity
  3. 600
  4. 18
  5. Torque
  6. Static
  7. Omni
  8. Gravity (Center of Gravity)
  9. Left and Right
  10. Friction

Section 4: Calculation Problems

  1. F = 6 × 3 = 18 Newtons
  2. a = 24 ÷ 12 = 2 m/s²
  3. F = 8 × 4 = 32 Newtons
  4. p = 7 × 3 = 21 kg·m/s
  5. Robot X: 4 × 5 = 20, Robot Y: 10 × 2 = 20, Tie!
  6. Output = 2 × 36 = 72 N·m
  7. Distance = 600 × 319 = 191,400 mm = 191.4 meters
  8. Ratio = 60 ÷ 12 = 5:1
  9. 200 × 319 = 63,800 mm/min ÷ 60 = 1,063 mm/s = 1.06 m/s
  10. 100 × 319 ÷ 60 = 532 mm/s = 0.53 m/s

Section 5: Scenario-Based Questions

  1. A, B, C - All help resist pushing (D would make it worse!)
  2. B - BLUE gives more speed
  3. B - Lower center of gravity = more stable
  4. C - BLUE for speed
  5. B - Momentum carries the robot past the target
  6. B - Dust reduces friction
  7. Suggested priority: 2, 1, 4, 3 (Torque first for blocking, then stability, then speed, then turning)
  8. B - Complement your partner with defense

Section 6: Match the Terms

Set A: 1-C, 2-A, 3-E, 4-F, 5-D, 6-B Set B: 7-H, 8-I, 9-J, 10-G Set C: 11-L, 12-K, 13-M Set D: 14-O, 15-P, 16-N

Section 7: Diagram Labeling

Diagram 1:

  • A = Motor Force (forward)
  • B = Friction (from floor pushing back)
  • C = Gravity (weight pulling down)
  • D = Normal Force (floor pushing up)

Diagram 2:

Setup 1 gives more torque because the output gear is larger than the input (3:1 ratio), which multiplies torque.

Diagram 3:

  • A = Traction wheel
  • B = Omni wheel
  • C = Mecanum wheel

Score Yourself

Section Your Score Possible
True/False ___ 15
Multiple Choice ___ 20
Fill in Blank ___ 10
Calculations ___ 10
Scenarios ___ 8
Matching ___ 16
Diagrams ___ 10
TOTAL ___ 89

Percentage: ___ ÷ 89 × 100 = ___%

  • 90-100%: Excellent! Ready for Tutorial 2.
  • 80-89%: Good job! Review missed concepts.
  • 70-79%: Review Tutorials 1.1-1.3 before continuing.
  • Below 70%: Re-read the tutorials and try again!

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