Question

Projectile Physic lab

Table 1:

	Trial 1	Trial 2	Trial 3	Average
Time (s)	0.4179	0.4032	0.4524	0.4245
Horizontal distance (m)	0.48	0.48	0.48	0.48
Vertical distance (m)	0.93	0.93	0.93	0.93

Table 2 :

	Trial 1	Trial 2	Trial 3	Average
Time (s)	0.4915	0.4782	0.4473	0.4723
Horizontal distance (m)	0.40	0.37	0.35	0.37
Vertical distance (m)	0.93	0.93	0.93	0.93

1- Calculate the initial and final speed of the ball using Newton’s second law for both tables.

2- Calculate the gravitation acceleration g practically for both tables.

3- Find the percentage error for the value of g found in the above question, knowing that the true value is 9.8.

Answer 1

The first table gives a time of 0.4245 s (4 significant figures), horizontal distance of 0.48 m (2 sig fig) and vertical distance of 0.93 m (2 sig fig)

The total distance is thus:

We should round this off later.

The initial speed is just this distance divided by time taken.

We need to round this off to 4 significant figures.

thus, speed = 2.465 m/s

Applying the same logic for the second table,

and thus speed is:

When rounded to 4 sig figures, we have speed = 2.119 m/s

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The formula for horizontal distance is:(using first table)

we know that: