An accelerated object is one whose velocity is changing. For a straight line mot

ID: 1785289 • Letter: A

Question

An accelerated object is one whose velocity is changing. For a straight line motion we can calculate the final speed (v) if we know the initial speed (v0), acceleration (a) and time (t) using the formula

v = v0 + at

When an object is thrown upward the effect of the downward acceleration of gravity is at first to reduce the objects upward speed. The upward speed decreases steadily until finally it is zero. The object is then at the top (peak) on its path, when the object is at rest for an instant.

For this case

final speed v = 0 and

acceleration a = -g = -9.8 m/s2 because it is a decelerated motion.

The object then begins to fall at increasing speed. Interestingly enough, something thrown upward at a certain speed will return to its starting point with the same speed (if we consider the air friction negligible), although the object is now moving in the opposite direction.

The distance under constant acceleration can be calculated using the following formula:

d = v0t + ½ at2

METHOD

We will measure the time the rocket is in an upward motion, from the time it leaves the ground, to its highest point (peak). We will also observe and measure the highest distance (peak) from the ground that the rocket reaches.

We will determine the initial speed of the rocket using the speed formula.

v0 = _______?

(Hint: use the final speed and acceleration values stated above.)

I have got my values for my table, but I need the initial speed for each

Time (peak)

in s

Initial speed

in m/s

Distance (peak)

in m

1/2 Alka-Seltzer

4.6

1 Alka-Seltzer

4.8

3/2 Alka-Seltzer

5.5

2 Alka-Seltzer

6.7