psf2 054 ☈ 12 June 2015 Name:

1. On Tuesday I accelerated a RipStik gathering the data seen below.
   
   1. _______________ _________ Based on the data, what was the acceleration of the RipStik?
   2. _______________ _________ Use the equation velocity ѵ = acceleration a × time t to determine my velocity after 4.87 seconds.
   3. _______________ _________ If I continued that same acceleration for 9.74 seconds, how far would I go in centimeters?
2. The data in the table and graphs are from a lab three ball dropping experiment.
   
   _______________ _________ According to the data and graphs, what is the acceleration of gravity?
3. A student rolled marbles into a line of five marbles.
   
   1. _________ If one marble collides with a line of five marbles on a ruler track, how many marbles are ejected (go out)?
   2. _________ If two marbles collide with a line of five marbles on a ruler track, how many marbles are ejected (go out)?
   3. Why do you think the marbles know what to do? Explain in your own words but do not use "magic" words that you cannot define. Write your answer using complete sentences.
4. Write Newton's first law of motion.
5. Write Newton's second law of motion.
6. Write Newton's third law of motion.
7. Which law did the "yurt" circle demonstrate and why?
8. The graph shows pulley data gathered by a student in physical science.
   1. Plot the data provided in the table on the graph below and draw a line through the points.
      
   2. ____________ Based on the data, what is the Actual Mechanical Advantage for the pulley system?
   3. ____________ The pulley system had four load lines. What is the Ideal Mechanical Advantage?
   4. ____________ Use the preceding two questions to calculate the efficiency of the pulley system.
   5. ______________ What was the likely cause of the efficiency being less than 100%?

$\text{Body mass index}=\frac{\text{mass in kg}}{{\text{height in meters}}^2}$
$\text{slope}=\frac{(y_2-y_1)}{(x_2-x_1)}$
$\text{percent error}=\frac{(\text{experimental value}-\text{expected value})}{\left(\text{expected value}\right)}$
Volume V = length l × width w × height h
mass m = density ρ × Volume V
$\rho =\frac{m}{V}$
distance d = velocity ѵ × time t
$\text{velocity}ѵ=\frac{\Delta d}{\Delta t}$
$\text{acceleration}a=\frac{\Delta ѵ}{\Delta t}$
velocity ѵ = acceleration a × time t
d = ½at²
d = ½gt²
where g is the acceleration of gravity, g = 979 cm/s²
Gravitational Potential Energy GPE = mgh
acceleration of gravity g = 979 cm/s²
Kinetic Energy KE = ½mѵ²
momentum = mass m × velocity ѵ
Force F = mass m × acceleration a
$\text{efficiency}=\frac{\text{Actual Mechanical Advantage}}{\text{Ideal Mechanical Advantage}}$