Two bodies moving and joint work
Find the distance between two bodies moving at once, and the time for joint work, from a table and a solving plan. Section: Grade 4, motion of two bodies and joint work; the fourth proportional is in another studio.
- أوكرانيا: الصف ٤
- روسيا: الصف ٤
لم يُترجَم هذا المختبر إلى هذه اللغة بعد.
الدليل
In Ukrainian Grade 4 pupils solve problems about two bodies moving at once: towards each other, in opposite directions and in the same direction. Plan: 1) v₁ · t = s₁; 2) v₂ · t = s₂; 3) s₁ + s₂ = s (the distance asked).
If the bodies move towards each other or apart, the distance between them changes by the sum of their ways. In the same direction it changes by the difference of the ways.
Joint-work problems are solved like motion problems: find how much each does in 1 day, then both together. The work is like the distance, and the daily output is like the speed.