This is a follow from a post i made yesterday. The question is:(adsbygoogle = window.adsbygoogle || []).push({});

2 particles are projected vertically up one after another from the same point at same initial speed u. T is the time interval between the 2 projections, where T<2u/g. Find what further time elapses before the particles collide, and find their speeds immediately before impact.

The equations i have found so far are for distance travelled

x= -0.5gt^2 + ut.

However i have realised this formula is for the distance the particle has travelled rather then the height reached. Since i need to find the time when the particles will collide (ie when they are at the same height) i am stuck as i think the formula is no use?! Please help

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# Projectile please help

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