Events & Promotions
|
|
GMAT Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized
for You
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Jun 1006:00 AM PDT
-06:15 PM PDT
Register for the GMAT Club Virtual MBA Spotlight Fair – the world’s premier event for serious MBA candidates. This is your chance to hear directly from Admissions Directors at nearly every Top 30 MBA program..- Jun 10
10:00 AM PDT
-11:00 AM PDT
Scoring 715 on the GMAT Focus Edition requires more than just learning formulas, memorizing concepts, or solving hundreds of questions. In this episode, Nishant shares how he improved his GMAT preparation by focusing on application of concepts, and more. 
Jun 1111:00 AM EDT
-01:00 PM EDT
TTP GMAT OnDemand gives serious students 400+ hours of expert video instruction, the full TTP course, AI support, weekly office hours, and a 715+ score guarantee—all built for elite GMAT score improvement.
Jun 2207:30 PM EDT
-09:30 PM EDT
Master the GMAT with expert live instruction, a personalized study plan, and real-time support. Includes 40 hours of online classes plus 6 months of access to the TTP GMAT OnDemand video course. Class date: Mon/Wed June 22, 2026 →August 26, 2026
25 Dec 2025, 09:00
Kudos
Bookmarks
Distance: 12
Intensity: 2
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
55%
(hard)
Question Stats:
71% (01:53) correct
29%
(02:21)
wrong
based on 319
sessions
History
Date
Time
Result
Not Attempted Yet
12 Days of Christmas Competition
This question is part of our holiday event
Win $40,000 in prizes: courses, tests, and more
A point light source shines equally in all directions. The light intensity measured at a sensor is inversely proportional to the square of the distance from the source.
When the distance is 6 meters, the intensity is 8 units.
Select for Distance a distance in meters and select for Intensity an intensity in units that would be jointly consistent with the given information, Make only two selections, one in each column.
I31-38
| Distance | Intensity | |
| 2 | ||
| 4 | ||
| 12 | ||
| 16 | ||
| 24 | ||
| 32 |
ShowHide Answer
Official Answer
Distance: 12
Intensity: 2
25 Dec 2025, 10:00
Kudos
Bookmarks
A point light source shines equally in all directions. The light intensity measured at a sensor is inversely proportional to the square of the distance from the source.
When the distance is 6 meters, the intensity is 8 units.
Select for Distance a distance in meters and select for Intensity an intensity in units that would be jointly consistent with the given information, Make only two selections, one in each column.
We are given that the intensity is inversely proportional to the square of distance, so Intensity = k/Distance^2, where k is a constant.
Since when D = 6 meters, I = 8 units, we have 8 = k/6^2, which gives k = 288.
Now check the options to find a pair (D, I) such that I = 288/D^2. Only (12, 2) fits. Thus, Distance = 12 meters and Intensity = 2 units.
GMAT-Club-Forum-e33ipien.png [ 12.12 KiB | Viewed 1689 times ]
When the distance is 6 meters, the intensity is 8 units.
Select for Distance a distance in meters and select for Intensity an intensity in units that would be jointly consistent with the given information, Make only two selections, one in each column.
GMAT Club Official Explanation:
We are given that the intensity is inversely proportional to the square of distance, so Intensity = k/Distance^2, where k is a constant.
Since when D = 6 meters, I = 8 units, we have 8 = k/6^2, which gives k = 288.
Now check the options to find a pair (D, I) such that I = 288/D^2. Only (12, 2) fits. Thus, Distance = 12 meters and Intensity = 2 units.
Attachment:
GMAT-Club-Forum-e33ipien.png [ 12.12 KiB | Viewed 1689 times ]
General Discussion
25 Dec 2025, 09:44
Kudos
Bookmarks
Intensity is inversely proportional to distance^2 from source
Let x is a constant
I=x/(d^2)
x= I.d^2
When d=6, i is 8 units
x= 8*(6^2)=288
Check given options
If d=4...Intensity= 288/16=18
If d=12...Intensity= 288/144=2.......available in options
Distane= 12 and Intensity= 2
Let x is a constant
I=x/(d^2)
x= I.d^2
When d=6, i is 8 units
x= 8*(6^2)=288
Check given options
If d=4...Intensity= 288/16=18
If d=12...Intensity= 288/144=2.......available in options
Distane= 12 and Intensity= 2
