Problem P. 4315. (February 2011)

P. 4315. Two balls of masses m₁=0.173 kg and m₂=0.2 kg are moving and the direction of their motion is perpendiculer to each other. Their speeds are v₁=10 m/s and v₂=5 m/s, respectively. After the collision the ball of mass m₁ stops. What will the speed of the ball of mass m₂ be after the collision?

(4 pont)

Deadline expired on March 10, 2011.

Sorry, the solution is available only in Hungarian. Google translation

Megoldás. Az ütközés előtt a két golyó együttes lendülete a merőleges haladási irány miatt \(\displaystyle \sqrt{m_1^2v_1^2+m_2^2v_2^2}\). Az ütközés után a teljes lendületet a 2-es golyó viszi el, ezért ennek sebessége \(\displaystyle v_2'=\sqrt{\left( \frac{m_1}{m_2} \right)^2v_1^2+v_2^2}\approx 10\) m/s.

Statistics:

171 students sent a solution.
4 points:	106 students.
3 points:	24 students.
2 points:	10 students.
1 point:	26 students.
0 point:	1 student.
Unfair, not evaluated:	4 solutionss.

Problems in Physics of KöMaL, February 2011