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IBC Quiz #176

Winners of the previous Quiz

24/10/2025

Likhith g pawar

Likhith g pawar

Class 9

Vidya jyothi school

Tasib khan

Tasib khan

Class 6

Tahir public school

Tejaswani Panchal

Tejaswani Panchal

Class 8

NPS Kengeri

Adisha R Gowda

Adisha R Gowda

Class 7

Prudence International School , Tumkur

Raneetha.M

Raneetha.M

Class 5

SRI sharada english school

Pratham gowda gk

Pratham gowda gk

Class 8

Mother Teresa international school

Harish

Harish

Class 9

PREETHI PUBLIC SCHOOL

Ananya Gowda G P

Ananya Gowda G P

Class 8

G.R.International Public school dodderi

L Kushil Prasad

L Kushil Prasad

Class 4

St Michel's English School, Kanakapura

Aishani Bhat

Aishani Bhat

Class 5

KSVK International School

Note: Quiz prizes will be awarded to ten randomly selected students who submit correct answers before the deadline. Winners will be declared on the website and the weekly newsletter.

Winner cup

October 24, 2025

Q1.

Maya, a student, is building an automated conveyor system for her STEM project. While trying to understand and improve how the system performs during unexpected interruptions, she notes the following: 

  • Boxes move on a conveyor belt to a platform, where a robotic arm picks each box and packs it into cartons. 

  • During testing, she notices that if the robot’s battery runs out, it stops and immediately sends a signal to the controller. This signal takes a short time to reach the controller, which then instructs the conveyor to stop. However, the conveyor continues moving briefly before coming to a complete halt due to its momentum. 

  • Once the conveyor has stopped, Maya’s assistant replaces the robot’s battery, a process that takes 15 seconds. 

  • After the battery is replaced, the robot sends another signal to the controller, which instructs the conveyor to start moving again. 

Maya wants to make sure that: 

  1. Boxes never collide on the platform during this stop, replace and restart sequence. 

  1. She also aims to calculate how long the conveyor will remain stopped during this process. 

Details: 

  • Conveyor speed = 0.6 m/s 

  • Signal delay (robot → controller) = 1.5 s each time 

  • Conveyor stopping distance = 0.6 m 

  • The platform can safely hold only one box at a time 

  • Robot battery replacement time = 15 s 

(a) What is the minimum distance between consecutive boxes on the conveyor so that no collision occurs? 

(b) After the robot stops, how many seconds later will the conveyor start moving again? 

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Q2.

In a packaging unit, a conveyor belt continuously moves boxes to a platform where a robotic arm picks them up and packs them into cartons. 

If the robot stops functioning, it immediately sends a signal to the controller, which then instructs the conveyor to halt. 

However, due to signal delay and mechanical stopping distance, the conveyor does not stop immediately. 

Maya wants to ensure that no two boxes collide on the platform during this delay. She needs to calculate the minimum distance between consecutive boxes on the conveyor. 

Details: 

  • Conveyor speed = 0.6 m/s 

  • Signal delay (robot → controller → conveyor) = 1.5 seconds 

  • Conveyor stopping distance after receiving the stop command = 0.6 m 

  • The platform can safely hold only one box at a time 

Question: 

What is the minimum distance that should be maintained between consecutive boxes on the conveyor so that no collision occurs if the robot stops working? 

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October 17, 2025

Q1.

A large manufacturing facility operates five independent water recycling units — Unit 1, Unit 2, Unit 3, Unit 4 and Unit 5 - each treating industrial process water for different production lines. All units employ the same three-stage purification system to clean water for machinery cooling and equipment operation. 

Treatment Process: 

  • Stage 1 (Sedimentation): Removes large particles; the flow rate depends on tank cleanliness and recent maintenance. 

  • Stage 2 (Biological Filter): Eliminates organic contaminants; performance varies with the health of the bacterial colony, water temperature, and pH level. 

  • Stage 3 (Chemical Treatment): Provides final purification using chlorination; manual dosing may be required if automation fails. 

Operational Rules: 

  • All units operate in batch mode -Water cannot progress to the next stage until the current stage is finished. 

  • All units must process 100,000 litres of contaminated water. Processing speed varies by stage and by the condition of the equipment. 

  • If any stage takes more than 500 minutes, add 10% to that stage's processing time due to operator fatigue and reduced system efficiency during extended operations. (Note: This rule does not apply if Stage 3 exceeds 500 minutes, as there is no subsequent stage.) 

  • Each stage also includes 5 minutes of random downti

Today’s Unit-Specific Conditions and Adjusted Flow Rates: 

Unit 

Stage 1 Flow Rate (L/min) 

Stage 1 Status 

Stage 2 Flow Rate (L/min) 

Stage 2 Status 

Stage 3 Flow Rate (L/min) 

Stage 3 Status 

Unit 1 

300 

Sedimentation tank cleaned yesterday → +20% flow 

180 

Normal 

200 

Normal 

Unit 2 

280 

Normal 

150 

Bacterial colony underperforming due to temperature drop → operating at 75% capacity 

220 

Normal 

Unit 3 

300 

Normal 

190 

Normal 

90 

Automated chemical system malfunction → 50% slower 

Unit 4 

260 

Normal 

185 

Normal 

210 

Normal 

Unit 5 

270 

Normal 

157.5 

Filter partially clogged → operating at 90% capacity 

195 

Normal 

 

After factoring in all adjustments, recovery and downtime, which unit completes the full purification process first and which completes it last?

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Q2.

A large manufacturing facility operates five independent water recycling units — Unit 1, Unit 2, Unit 3, Unit 4 and Unit 5 - each treating industrial process water for different production lines. All units employ the same three-stage purification system to clean water for machinery cooling and equipment operation. 

Treatment Process 

  • Stage 1 (Sedimentation): Removes large particles; flow rate determines processing capacity. 

  • Stage 2 (Biological Filter): Removes organic contaminants; efficiency depends on the health of the bacterial colony. 

  • Stage 3 (Chemical Treatment): Final purification using chlorination. 

All units must process 100,000 litres of contaminated water. Processing speed varies by stage and by the condition of the equipment. 
Note: All units operate in batch processing mode — water cannot proceed to the next stage until all 100,000 litres have completed the current stage. 

Unit-Specific Conditions (Today) 

  • Unit 1: Sedimentation tank was cleaned yesterday, removing accumulated sediment buildup → Stage 1 operates 20% faster than baseline flow rate. 

  • Unit 2: Bacterial colony in Stage 2 filter underperforming due to temperature drop → operating at only 75% of normal capacity. 

  • Unit 3: Automated chemical system malfunctioned this morning → Stage 3 requires manual dosing (50% slower). 

  • Units 4 & 5: All systems operating normally. 

Performance Data: 

Unit 

Stage 1 Flow Rate (L/min) 

Stage 1 Status 

Stage 2 Capacity (L/min) 

Stage 2 Status 

Stage 3 Rate (L/min) 

Stage 3 Status 

Unit 1 

250 

+20 % boost 

180 

Normal 

200 

Normal 

Unit 2 

280 

Normal 

200 

75 % capacity 

220 

Normal 

Unit 3 

300 

Normal 

190 

Normal 

180 

50 % slower 

Unit 4 

260 

Normal 

185 

Normal 

210 

Normal 

Unit 5 

270 

Normal 

175 

Normal 

195 

Normal 

 

Which treatment unit completes the full purification process first, and which completes it last?

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