P Lab Free Fall

An object is dropped from rest. Which equation correctly describes the distance it falls after time t?

y=1/2​gt^2

In a free fall experiment, what does the slope of the distance vs. time squared graph represent?

Half of gravitational acceleration

If the slope of your distance vs. t2t^2t2 graph is 4.95, what is your experimental value for g?

9.80 m/s²

What is assumed about the initial velocity in the free fall lab?

It is zero

Why do we square the time values in this experiment?

To create a linear relationship with distance

Why can we ignore air resistance in this lab?

Air resistance is small for short distances and slow speeds, so it doesn’t significantly affect the motion — we assume it’s negligible.

If the equation from your graph is y=4.87xy = 4.87xy=4.87x, what is the value of g?

From y=4.87x, skope = 4.87
→ g = 2 × 4.87=9.74 m/s2

What does it mean if your R² value from a linear regression is close to 1?

R² close to 1 means the data fits the line very well — strong correlation and consistent data.

An object is dropped and falls 1.25 meters in 0.51 seconds.
Use the formula to estimate g from this data:

g=2y/t²

g=2(1.25)/(0.51)² = 2.5/ 0.2601 = 9.61

A student recorded the following drop times from the same height (1.5 m):
Trial 1: 0.55 s
Trial 2: 0.61 s
Trial 3: 0.58 s

a) Calculate the average time
b) Calculate t² using your average time
c) Use g = 2y/t²​ to estimate g

a) Average= 0.55 + 0.61+ 0.583/3=0.58

b)t²=(0.58)²=0.3364 S²

c) g=2(1.5)/0.3364≈8.91 m/s²

Your lab group got a graph equation:

y=5.1x

where y = distance and x = t²
What is the value of g?

g=2×5.1=10.2 m/s2​