John203

Hey guys, when it refers the time at a "point of impact," is it talking about when acc. = 0? Thanks. (in the problem, we are given s(t).

TheMathProf

I'm not familiar with a problem that uses this terminology, but I would think the "point of impact" would be the place where the position of a function reaches a certain value.

For instance, if the initial position was given as being 80 for a ball being thrown against a wall, then I would think that the point of impact would be when the initial position reached 0.

From a physics perspective, the velocity or acceleration of the ball wouldn't necessarily be approaching 0 as the ball approached the wall, but the velocity and acceleration would change because of a new force applied to the ball (that force being the wall).

At least that's how I would interpret that.

John203

We were given the s(t) equation and its initial velocity of 112 m/s. Does that help any? Thanks.

fignewton

At the point of impact, the velocity would have to go to zero (and possibly change sign), so I suppose you could take the derivative of s(t), set to zero, and solve for t...

In real life, the point of impact would happen a little before v=0...