BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

Target Test Prep · GMAT

Choose how you want to prepare

Learn live with an expert or move at your own pace. Every option includes the complete TTP study system.

★★★★★5.0559 reviews
Vote for Target Test Prep, Newsweek Readers’ Choice Awards 2026
NEWSWEEK READERS’ CHOICE 2026

BIG NEWS! Target Test Prep has been nominated, and they’d love your vote!

TTP has worked incredibly hard to build the best test prep experience possible, and winning Newsweek’s 2026 Readers’ Choice Award for Best Test Prep would mean a lot to them. If TTP has helped you, they’d be incredibly grateful for your vote. You can vote once each day through September 9.

Vote for TTP
GMATLiveTeach 7 seats left
Chris Peckover
NEXT LIVE COHORT

Oct 13 to Jan 7, 2027

with Chris Peckover

Schedule
Tue, Thu · 8:00 to 10:00 PM ET
Included
40 live hours + 6 months of GMAT OnDemand
  • Live instruction and real-time questions
  • Class recordings and assigned practice
View class & enroll
Limited cohort · enrollment openTarget Test Prep
EALiveTeach 5 seats left
Logan Thompson
EXECUTIVE ASSESSMENT

Sep 6 to Dec 6, 2026

with Logan Thompson

Schedule
Sun · 9:30 AM to 12:30 PM ET
Included
40 hours of live online classes plus six months of access to the complete TTP EA OnDemand course.
  • 165+ EA Score Guarantee
  • 4,100+ Quant, Verbal, and Integrated Reasoning practice questions
  • 400+ hours of in-depth video lessons
  • 3,000+ step-by-step video solutions
View EA class & enroll
Limited cohort · enrollment openTarget Test Prep
GMATOnDemand Start anytime
SELF-PACED MASTERCLASS

Target Test Prep GMAT OnDemand

Complete access from day one. Study on your schedule.

715+ score guarantee
$0to start then $127/mo
  • Personalized study plan and analytics
  • Thousands of lessons and practice questions

Compare the format, schedule, and included access before enrolling. Prices and seat counts shown reflect the supplied offer details.

Fifth Force ..

Expert replies
by kaulnikhil » Fri Dec 25, 2009 11:46 pm
Before 1986 physicists believed they could describe
the universe in terms of four universal forces.
Experiments then suggested, however, a flfth
universal force of mutual repulsion between particles
of matter. This fifth force would explain the
occurrence in the experiments of a smaller
measurement of the gravitational attraction between
bodies than the established theory predicted.
Which one of the following, if true, most strengthens
the argument that there is a fifth universal force?
(A) The extremely sophisticated equipment used
for the experiments was not available to
physicists before the 1970s. (
B) No previously established scientific results are
incompatible with the notion of a fifth
universal force.
(C) Some scientists have suggested that the alleged
fifth universal force is an aspect of gravity
rather than being fundamental in itself.
(D) The experiments were conducted by physicists
in remote geological settings in which factors
affecting the force of gravity could not be
measured with any degree of precision.
(E) The fifth universal force was postulated at a time
in which many other exciting and productive
ideas in theoretical physics were developed,
[spoiler]
Why is C wrong ..If the fifth force is an aspect of gravity ... wouldn't it help in the measurement of gravity ???[/spoiler]
Join the discussion
Source: — Critical Reasoning |

by linkinpark » Sat Dec 26, 2009 5:27 am
I picked B,

with C, don't know if my reasoning is correct - if fifth force was aspect of gravitational force doesn't it indicate that it was existing force and not new ?
Join the discussion

by kellygreen » Sat Dec 26, 2009 10:00 am
I lean toward B also. What's the official answer?

I guess C is wrong because the question asks for something that supports the existence of a 5th force, but C would say that instead of a 5th force, the physicists are just noticing something that's already part of gravity, one of the other 4 forces, so it actually hurts the argument for a 5th force.
Join the discussion

by Testluv » Sat Dec 26, 2009 3:43 pm
The correct answer is definitely choice B. We can use the denial test. What would happen to the argument if previously established results WERE inconsistent with the notion of a fifth force? Then, the argument that there is a fifth force would definitely be weakened. Because the denial of chioce B clearly weakens the argument, choice B must be a strengthener.

@kaulnikhil: look at the scope of the argument; the question stem instructs you to find a choice that will strengthen the argument that there IS a fifth force--not that gravity can be measured.
Kaplan Teacher in Toronto
Join the discussion

by kaulnikhil » Sun Dec 27, 2009 10:33 am
Thanks a lots guys ...OA is B
Join the discussion

by kaulnikhil » Sun Dec 27, 2009 10:34 am
Thanks a lots guys ...OA is B
Join the discussion

by vinni.k » Tue May 08, 2012 12:50 am
Today, I came across this question from veritas prep, and I would be glad, if any expert can help in negating choice C.

My stand on C:-
I believe that if i negate choice C, it is incorrect as an answer because some is very broad term in negation. Some can mean 99 scientists suggest and 1 scientist does not suggest or 1 scientist suggests and 99 scientists do not suggest.

Hence, it is incorrect (not strengthening or weakening. But I am looking for an explanation from expert.

Thanks & Regards
Vinni
Join the discussion

by vk_vinayak » Tue May 08, 2012 9:19 am
Why is A wrong?

Is it because of 1970s? If 1986 (instead of 1970) was mentioned in A, will it be correct?
- VK

I will (Learn. Recognize. Apply)
Join the discussion

by ice_rush » Tue May 08, 2012 11:32 am
Hi vk_vinayak,

even if the year were to change to 1986 in (A), it would still be wrong.



hope this helps.
Join the discussion