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Motion, Forces, Orbits-Gravity, Simple Machines Study GuideAnswer the following questions. Be sure your definitions are complete and your own words. Copying down content word for word off websites/PowerPoints is plagiarism and will not be accepted. A zero will be put in the gradebook that will not be a grade you can change.

1. What is the difference between; speed, velocity, and acceleration? Speed: scalar (number value only). How fast something is moving (d/t) distance / time Velocity: vector (number with direction). How fast something is moving in a particular

direction (d/t) Acceleration: change in velocity (v (final)-v(initial))/time. Since acceleration is change in

velocity, velocity is a vector; acceleration is a vector as well. 2. How are distance and displacement similar? How are they different? Distance: The path you take, the length. It has curves and changes to directions. Displacement: the length from starting point to ending point connected by a straight line.

3. Which of the following are a vector quantity or a scalar quantity? Justify each one. (Speed, Velocity, Acceleration)

Speed: scalar (number value only). How fast something is moving (d/t) distance / time Velocity: vector (number with direction). How fast something is moving in a particular

direction (d/t) Acceleration: change in velocity (v(final)-v(initial))/time. Since acceleration is change in

velocity, velocity is a vector; acceleration is a vector as well. 4. Define free fall and explain why you couldn’t use it for your acceleration lab. A free falling object is an object that is falling only under the influence of gravity. Free-

falling objects do not encounter air resistance.o All free-falling objects (on Earth) accelerate downwards at a rate of 9.8 m/s/s

In the lab our cars were rolling down a ramp (rolling friction) and in the egg drop lab the device was created to include a parachute which increases air resistance.

5. What is the difference between force and net force? Force: a push or a pull that that can change the velocity of a mass. A   net force: the sum of all   forces   acting on an object. An unbalanced   force   ( net force ) that acts on any object changes will change its

speed/direction

6. Define friction and explain the 4 different types of friction. Static Friction: Static friction is when objects are resting on a surface. An example,

would be if you are hiking in the woods, there is static friction between your shoes and the trail each time you put down your foot. Without this static friction, your feet would slip out from under you, making it difficult to walk. In fact, that’s exactly what happens if you try to walk on ice. That’s because ice is very slippery and offers very little friction.

Sliding Friction: Sliding friction is when friction occurs over objects as they are sliding over a surface. Sliding friction is weaker than static friction. That’s why it’s easier to slide a piece of furniture over the floor after you start it moving than it is to get it moving in the first place. Example would be sledding or ice skating.

Rolling Friction: Rolling friction is when friction occurs on objects when they are rolling over a surface. Rolling friction is much weaker than sliding friction or static friction. This explains why most forms of ground transportation use wheels, including bicycles, cars, 4-wheelers, roller skates, scooters, and skateboards. Ball bearings are another use of rolling friction

Fluid Friction : Fluid friction is when the friction that acts on are moving through a fluid. Fluids include liquids and gases. When you are swimming you can feel the   resistance   of the water against your hand. Think about a skydiver they are falling toward Earth with a parachute.   Resistance   of the air against the parachute slows the descent (just like the egg drop lab). The faster or larger a moving object is, the greater is the fluid friction resisting its motion. That’s why there is greater air resistance against the parachute than the skydiver’s body.

7. What is air resistance? How does it impact your egg drop? How does it impact Freefall? Resistance   of the air against the parachute slows the descent (just like the egg drop lab).

This helps the egg from breaking because it’s traveling at a slower speed. Because of the resistance we do not have a freefall, as the only force acting on an object in freefall is gravity.

8. What is gravity? Gravity is a force of attraction between two things that have mass. Depending on the

mass and the distance between them the force changes. If the masses are large and have a small distance between them then the force is great. If the mass is the same and the distance between them is great, then the strength of   gravity   between two objects depends on their mass and their distance apart. Earth's   gravity constantly pulls matter toward the center of the planet

9. Define terminal velocity. Terminal velocity is the final maximum velocity an object can reach because of air

resistance. 10.Explain what projectile motion is. Without gravity present if you were to throw a ball it would travel in a straight line and

continue. However, if you throw an object here on Earth the path the ball takes is rounded as the force of gravity pulls the ball back down to the surface. That curved path is projectile motion.

11.Explain each of Newton’s Laws of motion. Inertia (Newton’s), Newton’s 2nd Law of Motion, Newton’s 3rd Law of Motion.

Newton’s First Law of Motion (Law of Inertia): An object in motion/at rest will stay in motion/at rest until a force acts upon it.

Newton’s Second Law of Motion: The acceleration of an object depends on the force and the mass of an object (F=m*a). Force= mass * acceleration.

Newton’s Third Law of Motion: For every action there is an equal and opposite reaction.

12.What is Newton’s Universal Gravitational Law. Newton’s Universal Gravitational law is a   law   stating that any two masses/objects will

attract each other with a force equal to a constant (constant of   gravitation ) multiplied by the product of the two masses and divided by the square of the distance between them. Fg=G( m1 *m2 / d

2 ) F g= force of Gravity G= gravitational constant (6.67*10 -11 ) M 1= mass of one object M 2= mass of second object d= distance between objects If the distance is increased, then the force of attraction is decreased. If the distance is

decreased, then the force of attraction is increased. As the mass increases so does the force of attraction.

13.How is mass different from weight? Mass of an object never changes as it is the amount of matter something has. Weight is

the measure of the pull of gravity on an object. So, if I were to go to the moon, my mass will not change but my weight will as the force of gravity on the moon is not as strong.

14.What is momentum? What is the Law of Conservation of Momentum? Momentum is simply mass in motion. p=m*v p= momentum m= mass v= velocity The Law of Conservation of Momentum: states that if the momentum is lost by one object

is gained by another object, then the total amount of momentum is constant. So, the total momentum before a collision is the same as the total momentum after.

15.Define each of the following:

Electromagnetic Force: is a force that acts between charged particles and is the combination of all electrical and magnetic forces. The electromagnetic force can be attractive or repulsive and is found in light, television, radio, UV, and so on.

Strong Nuclear Force: Operate over a very short range, the attractive force is found in the nucleus and is the force that holds the particles (protons or neutrons-nucleons) together. Strongest force in nature.

Weak Nuclear Force: Operate over a very short range, the weak force plays a greater role in things falling apart, or decaying. The weak force, or weak interaction, is stronger than gravity, but it is only effective at very short distances. It acts on the subatomic level and plays a crucial role in powering stars and creating elements. It is also responsible for much of the natural radiation present in the universe

Gravitational Force: movement, or a tendency to move, toward a center of attractive force, as in the falling of bodies to the earth.

Centripetal Force: the force that is necessary to keep an object moving in a curved path and that is directed inward toward the center of rotation. a string on the end of which a stone is whirled about exerts centripetal force on the stone if you cut the string then the stone will fly off in a tangent angel.

16.How is work different from power? Work: using a force to move an object a distance (force and motion in same

direction) W= F*d (work is equal to force applied to an object times the distance traveled). Units are Newton-Meters or more commonly called Jules (J)

Power: rate at which work is done. Calculated by (W/t) work divided by time it took. Units are Watts (w).

17.What is the definition of a machine? Machine: a device that helps make work easier by accomplishing one or more of

the following: transfer force from one place to another, change direction of force, increase magnitude of force, increase distance or speed of a force

18.What is an input force and how is it different from an output force? How is it similar to input and output distances? Input and output arms?

Input force: is the force applied to a machine Output force: is the resulting force you get out of the machine. Input distance:  Distance the force acts through Output distance: number of times that a machine increases an input force Input arm: The side of a lever on which force is applied. Output arm: The side of a lever on which force is applied.

19.What is Actual Mechanical Advantage (AMA) and how is it different from Ideal Mechanical Advantage (IMA)? How is it calculated?

Mechanical advantage: is the measure of how much easier the task has become. Ideal Mechanical advantage: is with no loss due to friction

i. IMA= input distance/output distance (input distance divided by output distance)

Actual Mechanical advantage: takes loss of friction into considerationi. AMA= output force/input force

20.What is efficiency? Is there any machine that is 100% efficient? Explain your answer. Efficiency: The percentage of the work input that becomes work output. E= (Work Output/Work Input) x 100% Because friction is always present, the actual mechanical advantage of a machine is

always less than the ideal mechanical advantage. Because there is always some friction, the efficiency of any machine is always less than 100%.

21.Define Lever:

WORK

NOT WORK

Lever: rigid bar that rotates around a fixed point called a fulcrum, can be curved or straight

22.Draw and label: 1st class lever, 2nd class lever, and 3rd class lever. Explain the similarities and differences between them.

There are three types or classes of levers, according to where the load and effort are located with respect to the fulcrum. 

Class 1 has the fulcrum placed between the effort and load,  Class 2 has the load in-between the effort and the fulcrum, and  Class 3 has the effort between the load and the fulcrum

23.What is a fulcrum? What is an input arm? What is an output arm? Fulcrum: the point on which a lever rests or is supported and on which it pivots. Input arm: distance between the input force and the fulcrum Output arm: distance between the output force and the fulcrum

24.What is a wheel and axel? Draw and label. Wheel and axel: consists of a wheel attached to a smaller axle so that these two

parts rotate together in which a force is transferred from one to the other.

25.Define inclined plane. Why are a wedge and a screw considered to be modifications of an inclined plane?

a plane inclined at an angle to the horizontal. A sloping ramp up which heavy loads can be raised by ropes or chains.

A wedge looks like two inclined planes stuck together. The edge of a wedge is often called the blade. The big difference between a wedge and an inclined plane is that, while the inclined plane stays still, a wedge moves to do its work. 

The screw consists of a narrow-inclined plane wrapped around a cylinder.

26.What is a pulley? What does it do? Besides being able to move or not move what are the

differences between a fixed and a moveable pulley The pulley is really a wheel and axle with a rope or chain attached.

A pulley makes work seem easier because it changes the direction of motion to work with gravity.

Moveable: rises and falls with the load that is being moved. A single moveable pulley creates a mechanical advantage; however, it does not change the direction of a force

Fixed: does not rise or fall with the load being moved. A fixed pulley changes the direction of a force; it does not create a mechanical advantage

27.What is the Law of Orbits (Kepler)?

The Law of Orbits: All planets move in elliptical orbits, with the sun at one focus.

28.What is the Law of Areas (Kepler)? A line that connects a planet to the sun sweeps out equal areas in equal times.

When the planet is closer to the sun, it moves faster, sweeping through a longer path in a given time.

29.What is the Law of Periods (Kepler)? If you square the 'year' of each planet, and divide it by the cube of its distance to

the Sun, you get the same number, for all planets. P2 = a.  It means that if you know the period of a planet's orbit (P = how long it takes the

planet to go around the Sun), then you can determine that planet's distance from the Sun (a = the semimajor axis of the planet's orbit).

Match the equation to the law/concept:1. Velocity2. Newton’s Second Law of Motion3. Momentum4. Law of Periods5. Acceleration6. Efficiency7. Actual Mechanical Advantage8. Ideal Mechanical Advantage

a. (Work output/work input) *100%b. Work/timec. Mass * velocityd. (Velocity final- velocity initial) / timee. Distance/timef. Force * Distanceg. Mass * Accelerationh. Output force/input forcei. Input force/output forcej. T2 = a3

k. G(m1 *m2)/ r2

9. Work10.Power11.Newton’s Universal Gravitational Law

Graph and explain the labs below by answer the questions provided. Lab #1: How does the height of a ramp affect the velocity of a car rolling down it?

Ramp Height (cm)

Time (s) Velocity (cm/s)

14 2.64 5.3019 1.93 9.8423 1.48 15.5427 1.18 22.8832 .86 37.21

1. Calculate the velocity in the table above.

2. From the title identify the manipulated (Independent variable)a. Heightb. Time

c. Velocityd. Distance

3. From the title identify the responding variable (dependent variable)a. Heightb. Time

c. Velocityd. Distance

4. What content needs to go into the introduction?a. In an introduction you need: purpose, process, background, and

hypothesis5. What would be a good hypothesis?

a. Any “If, then, because” statement that makes sense will be accepted6. What background should be included?

a. We should see some content about the definition of velocity, how it’s calculated, and if they add any reasoning in the hypothesis about forces/gravity they should also be explained.

7. Graph the data. Label each axis appropriately (which variable goes on the x-axis/which goes on the y-axis). Give the graph a title.

a. (Work output/work input) *100%b. Work/timec. Mass * velocityd. (Velocity final- velocity initial) / timee. Distance/timef. Force * Distanceg. Mass * Accelerationh. Output force/input forcei. Input force/output forcej. T2 = a3

k. G(m1 *m2)/ r2

Height versus Velocity

8. Now compare a velocity versus time graph of the same data. Label each axis appropriately (which variable goes on the x-axis/which goes on the y-axis). Give the graph a title.

Ramp height (cm)

Velocity (cm/s)2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 37

2468

10

Velocity versus Time

3230282624222018161412 10 11

Lab #2. How does acceleration of a car that travels down a ramp onto a flat surface change at different distances from the end of the inclined ramp?

Distance Trial 1 Trial 2 Trial 3 Average timeEnd of ramp 1.03s .91s 1.03s .99s50cm 1.45s 1.19s 1.30s 1.31s100 cm 1.55s 1.55s 1.63s 1.58s

2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 37

.25 0.5 1.0 1.25 1.5 1.75 2.0 2.25 2.5 2.75

Velocity (cm/s)

Time (s)

9. To answer the question what two concepts need to be calculated?a. Distance and timeb. Velocity and free fallc. Acceleration and distanced. Velocity and acceleration

10.Using the table above calculate the missing data from the previous question. Show your calculations and create a table for each of the concepts below.

Distance (cm)

Trial 1 (s) Trial 2 (s) Trial 3

(s)

Average time (s)

Average velocity (cm/s)

Average Acceleration (cm/s2)

120 1.03 0.91 1.03 0.99 121.21 122.44170 1.45 1.19 1.3 1.31 129.77 99.06220 1.55 1.55 1.63 1.58 139.24 88.13

Velocity= d/ t Acceleration = vf-vi/time

11.Graph the appropriate data to answer the question in Lab #2. Label each axis appropriately (which variable goes on the x-axis/which goes on the y-axis). Give the graph a title. Acceleration versus Time

12.What needs to be included in your “Analysis and Conclusion” for Lab #2? a. Analysis: hypothesis supported or not supported and possible errorsb. CER: One paragraph do not label claim, evidence, reasoning. It should be clear by

your write up.i. Claim answers the question. ii. Evidence (3 minimum) and must include trends in graphs (slope

increase/decrease steep or shallow) or numbers from the tablesiii. Reasoning (3 minimum) and must include the reason why your data supports

your claim. Why and how does the data support. This is when you use detailed explained vocabulary and concepts. If you stated gravity, forces, Newton’s Laws in your introduction it should be here in your reasoning.

.25 0.5 1.0 1.25 1.5 1.75 2.0 2.25 2.5 2.75

Time (s)

Acceleration (cm/s2)