Question

you stop the stopwatch at 4.0 s, but you notice a short time later that the same ant is at 0.81 m on the meter stick. Assuming that ant keeps going at the same velocity, how much time has passed since you stopped the stopwatch

Answer 1

The time elapsed since you stopped the stopwatch is 0.41 s.

Your question is not complete, it seems to be missing the following information;

"The velocity of the ant is 2 m/s"

The given parameters;

• velocity of the ant, v = 2 m/s

• change in position of the ant, Δx = 0.81 m

• initial time, t₁ = 4 s

• time when the ant was noticed, = t₂

Velocity is defined as the change in displacement per change in time of motion of an object.

$v = \frac{\Delta x}{\Delta t} = \frac{\Delta x}{t_2 - t_1} \\\\t_2 -t_1 = \frac{\Delta x}{v} \\\\t_2 - 4 = \frac{0.81}{2} \\\\t_2 - 4 = 0.405\\\\t_2 = 0.405 + 4\\\\t_2 = 4.405 \approx 4.41 \ s$

The time elapsed since you stopped the stopwatch is calculated as;

$t_{elapsed} = 4.41 \ s - 4\ s = 0.41 \ s$

Thus, the time elapsed since you stopped the stopwatch is 0.41 s.

Learn more here: brainly.com/question/18153640