Search found 57 matches

by SMMamun
Sat Dec 24, 2016 3:14 pm
Forum: Physics
Topic: About a problem from the BdPhO '17 category A
Replies: 1
Views: 1210

Re: About a problem from the BdPhO '17 category A

You are right; the problem contains an error.
by SMMamun
Fri Dec 23, 2016 8:36 pm
Forum: Physics
Topic: Photon and Tennis Ball
Replies: 1
Views: 984

Photon and Tennis Ball

Imagine you are sitting on a spaceship that is moving uniformly in a region of space where there is no gravity. You threw a tennis ball and a photon particle toward the roof of the spaceship. The ball is bouncing between the floor and the roof. The photon is bouncing between two mirrors – one on the...
by SMMamun
Fri Dec 23, 2016 4:00 am
Forum: Number Theory
Topic: Stuck! Pls help quick
Replies: 2
Views: 1132

Re: Stuck! Pls help quick

Where are you stuck? In this type of problem, it's convenient to start on GCD:

Let GCD be $g$ and the two numbers be $gx$ and $gy$, in which $x$ and $y$ are co-primes.
$gxy=7g$
$xy=7$
Think about what the values of $(x,y)$ could be.
Then you have just to solve
$gx+gy=392$
by SMMamun
Thu Apr 07, 2016 8:39 pm
Forum: Combinatorics
Topic: Combi-Spanish olympiad_1985
Replies: 2
Views: 1272

Re: Combi-Spanish olympiad_1985

Are you certain that n is a real number, not an integer? n as a real number will make the problem uninteresting.

Consider n an integer, and apply the Method of Mathematical Induction (গাণিতিক আরোহ পদ্ধতি).
by SMMamun
Tue Feb 16, 2016 3:19 pm
Forum: Junior Level
Topic: Exponents
Replies: 4
Views: 2950

Re: Exponents

It's essential to clarify all the constraints of a problem precisely. Why should we not consider negative and fractional values for a and b for this problem? For example, what's wrong with
$(a, b)=(-2, 10), (-32, 2), (1048576, \frac{1}{2})$?
by SMMamun
Mon Feb 01, 2016 3:17 pm
Forum: National Math Olympiad (BdMO)
Topic: Math Problem 1
Replies: 2
Views: 1414

Re: Math Problem 1

Your heuristic approach of solving the problem is commendable.
How about this approach: you assume the no. of students who scored less than 60 to be 'x' and then construct a simple algebraic equation? :)
by SMMamun
Tue Dec 29, 2015 8:08 pm
Forum: Physics
Topic: Relation between acceleration and deformation
Replies: 1
Views: 1250

Re: Relation between acceleration and deformation

It's always progressive for mutual discussion if we share our line of thought with the questions we pose. Otherwise, merely asking questions may fail to elicit sufficient interest among the forum members. Now about your question, you did not specify the directions of the forces . Anyway, both forces...
by SMMamun
Mon Jan 26, 2015 4:09 pm
Forum: Higher Secondary Level
Topic: Where did the other root go?
Replies: 7
Views: 2482

Re: Where did the other root go?

It didn't go anywhere. You have made an error in the root extraction formula for the quadratic form of equations. Please check again. :)
by SMMamun
Sun Nov 09, 2014 10:46 am
Forum: Physics
Topic: Errors in Galileo’s Thought Experiment?
Replies: 2
Views: 2123

Re: Errors in Galileo’s Thought Experiment?

"The contradiction, that "it will fall faster (for total mass is heavier) and it will fall slower (for the resistance by light object)", ended the discussion that initial assumption, that one was falling faster than another, isn't correct. That deduces what we wanted." — No, the supposed contradicti...
by SMMamun
Sat Nov 08, 2014 1:51 pm
Forum: Physics
Topic: Errors in Galileo’s Thought Experiment?
Replies: 2
Views: 2123

Errors in Galileo’s Thought Experiment?

"বিজ্ঞানকে জানার তিনটি সুনির্দিষ্ট পথ রয়েছে, প্রথমটি হচ্ছে যুক্তি তর্ক। একটা উদাহরণ দেয়া যাক: একটা ভারী জিনিস আরেকটা হালকা জিনিস উপর থেকে ছেড়ে দিলে দুটো কি একসাথে পড়বে নাকি ভারীটা আগে পড়বে? এই প্রশ্নের উত্তর খুঁজে বের করার জন্য কিন্তু কোনো বৈজ্ঞানিক সূত্রেরও প্রয়োজন নেই কোনো জটিল পরীক্ষা-নিরীক...