Newton’s Second Law of Motion Lukas Binau, Brandon Mock, Alexis Lundy, & Makenna Cooper

Major Concept Acceleration produced by a net force on a body is directly proportional to the magnitude of the net force, in the same direction of the net force, and inversely proportional to the mass of the body Acceleration= net force ÷ mass Net force is all forces acting upon a body for example friction and air resistance.

Historical Perspective Aristotle's defined motion as a chance factor. Motion involved a chance from potential to actual. That there was natural and unnatural motion. That some objects naturally rose or sink and unnatural recurring force to move. It wasn’t until the middle ages that Aristotle's beliefs of physics were being questioned, his ideas of physics lasted for about two millennial.

Application of Concepts When building aircrafts they need to implement aerodynamics to decrease the air residence on the aircraft. Their for increasing the acceleration. Using lightweight materials such as aluminum decrease the mass to increase the acceleration.

Think and Explain The difference between proportional and equal is that proportional is a constant ratio. The three engines would produce 1.5 m/s2 The truck would attain 1.25 m/s2 speed The rocket loses mass through the burning of the fuel Mass on the moon 1.67 kilograms The scale would read half of her weight for equal pull by rope. Force of ground pushing back would be decreased therefore friction will decrease

Cont. For the downward pressure is spread out. Sharp knife would have less friction from what it’s cutting The rope would have same pull from either side of him, and flag pole has less downward pull. The pressure of the large foot is more spread out, while smaller has to be strong enough to support the pressure The rock acceleration would become 0 at top of path.

Cont. If net force didn’t decrease terminal velocity would never be achieved, and acceleration has to decrease or terminal velocity wouldn’t exist. A skydiver would gain the most speed in the first second for from no speed of falling in the plane to instant falling, gain more distance in the ninth second because of the constant acceleration. The heavier one would land first for the speed would increase until air resistance is similar to weight of the ball allowing it to gain more distance.

Review Acceleration is change in motion and force creates motion All forces acting upon an object 30 N 20 N Double Halves Directly is increase makes increase and inversely increase makes decrease Acceleration is directly proportional to the magnitude of the net force. Acceleration= net force/mass

Cont. 20,000 N 15 N, net force is 0 N 100 N, 25 N per strand Kind of material/roughness, Opposite of motion Over 100 N, difference between force and friction Pressure is ratio of force over a surface and force is overall Narrow tire

Cont. Twice the mass No air resistance Coin has greater mass and less area for air resistance to act on it. 100 N of air resistance Equal Heavier needs more air resistance, lighter gains mass 25 N, 10 N, 0 N

Demonstration Hypothesis: How much force does the weight of a rock produce compared to a large marshmallow, when dropped from the same height into a bowl of flour? Materials:- Small Rock - Large Marshmallow - Flour (5 cups) - Stopwatch - Spring Scale - Meter Stick - Large Bowl Safety precautions: Don't drop the rock on your foot. Don't spill the flour.

Cont. Steps: 1) Measure Mass of Rock & Marshmallow (g) 2) Measure Height at Which Objects are Dropped (m) 3) With stopwatch in hand, drop the marshmallow from 1 meter in the air into the bowl of flour. Start the time when the marshmallow is released and stop the time when the marshmallow hits the surface of the flour. 4) Record Data (m/s) 5)With stopwatch in hand, drop the rock from 1 meter in the air into the bowl of flour. Start the time when the rock is released and stop the time when the rock hits the surface of the flour. 6) Record Data (m/s) 7) Calculate the force of both of the objects by using the formula: f=m*a (force=mass*acceleration)

Data I did three different trials of dropping the rock and the marshmallow into the flour to ensure accuracy. The first trial, it took the rock 0.38 seconds, the second trial took 0.43 seconds, and the third trial took 0.41 seconds. After doing proper calculations, I was able to come to the conclusion that in the first trial, the rock traveled at a speed of 2.63 m/s, 2.33 m/s in the second trial, and 2.44 m/s in the third trial. I then measured the mass of the rock (158.8 g) and the mass of the marshmallow (7 g) and used the formula: f=m*a to calculate the force of both objects hitting the flour. In the first trial, the marshmallow took 19.6 seconds to hit flour, 20.4 seconds in the second trial, and 20.8 seconds in the third trial. I was then able to do calculations and find out that in all of the trials, the marshmallow traveled at an approximate speed of 0.05 m/s. Rock: s/m m/s Trial 1 0.38 s 2.63 m Trial 2 0.43 s 2.33 m Trial 3 0.41 s 2.44 m Marshmallow: s/m m/s Trial 1 19.6 s 0.05 m Trial 2 20.4 s 0.05 m Trial 3 20.8 s 0.05 m Rock: f=(5.6)*(2.47) f=13.832 f=13.8 N Marshmallow: f=(7)*(0.05) f=0.35 N

Results After performing the experiment, I was able to determine that when the rock was dropped from 1 meter in the air, it traveled at an average speed of about 2.47 m/s. I was also able to determine that when the marshmallow was dropped from 1 meter in the air, it traveled at an average speed of about 0.05 m/s. With these numbers, I can use the formula: f=m*a to find the average force of the rock and marshmallow.

Results I am able to come to the conclusion that because the rock had more mass than the marshmallow, it traveled at a faster speed. The rock had a force of about 13.8 N and the marshmallow had a force of 0.35 N. Based on my calculations, I was able to come to the conclusion that the rock had more force on the flour than the marshmallow did. This is because the rock had more mass than the marshmallow, so the force built up quicker over the course of the time that it took to land in the rock, than it did with the marshmallow. I can now say that my hypothesis was correct based on my calculations.