Why s = v•t + ½at²?

EnderFleckyByEnderFlecky

Why does my teacher use this formula for b)? I know s = v•t and also s = ½at², but why does he add them together? He never discussed it with us, and the test is tomorrow. It also came up in the solutions to two other problems, but I don't understand it. s = v•t is for uniform motion, and s = ½at² is for uniformly accelerated motion. Why does he add them together?

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HansWurst45
HansWurst45
4 months ago

Because the car at b) is not accelerated from the standstill but has an initial speed.

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Spikeman197
Spikeman197
4 months ago

The principle of independence is allowed. You can add movements independently of each other.

Both formulas apply only when starting at 0 m, which is also only a special case. What if you want to overtake someone from 80 km/h and speed up to 120 km/h?

So even applies: s(t)=1⁄2at2+vt+s

3