Experiment 2 by Bayot, Lim, Uy

7/29/2019 Experiment 2 by Bayot, Lim, Uy

1/15

De La Salle UniversityCollege of Education

Science Education Department

PHY 583MEarth and Environmental Science

Experiment # 2

TRANSFORMATION OF MECHANICAL ENERGY

Members: Bayot, Joysol

Lim, Perlita

Uy, Roxanne

Prof: Dr. Cecil Galvez

Class Period: Sat, 8:00 am11:00 am

Date performed: 2/2/13


2/15

I. FSINTRODUCTIONA. BACKGROUND INFORMATION/THEORY AND CONCEPTS

The amount of energy in the universe remains the same. Energy can neither be created

nor destroyed (first law of thermodynamics). When energy is used, it is being

transformed from one form into another form/s (second law of thermodynamics).

There are many forms of energy and they are divided into two major categories. The

first one is the kinetic energy or the energy in motion and can be converted to and from

other forms. The other one is the potential energy, which is the stored energy within a

system or object. This is form can be converted and has the potential to do work.

One of the most common transformations is between the mechanical form of potential

and kinetic energy.

B. OBJECTIVES

This activity aims:

To learn about gravitational potential energy and kinetic energy of a dynamiccart along an inclined plane.

To investigate the transformation of mechanical energy of the cart. To investigate how the gravitational potential energy and the kinetic energy is

affected by increasing the release height of the cart keeping the mass of the cart

constant.

To investigate if the mechanical energy of the dynamic cart along an inclinedplane is constant.

C. HYPOTHESIS

If the cart descends from the top of the inclined plane, then its potential energy is

transformed into kinetic energy.


3/15

II. METHODSTART

SECURE MATERIALS

PREPARE SET-UP

USE SPARK COMPUTER PROGRAM

COLLECT DATA NEEDED FOR THE EXPERIMENT

GET THE ACCELERATION OF THE CART

CALCULATE KINETIC ENERGY

IS THE DATA

COMPLETE

AND N

ACCURATE?

Y

FIX SET UP

MAKE FURTHER STUDIES

END


4/15

III. Materials Used and experimental set-up


5/15


6/15

IV. DATAa. OBSERVATIONS in a DATA TABLE or CHART

Table 1.Shows the mass of the dynamic cart, minimum position, maximum position, and distance

covered by the 3 runs of the cart

Table 2. Shows the acceleration, distance covered, sin , height and gravitational potential

energy at the released pointof the 3 runs of the cart

Table 3. Shows the mass of the dynamic cart, final velocity, and kinetic energy at the lowest pointof the3 runs of the cart


7/15

Table 4. Shows the mass of the dynamic cart, height, final velocity, distance covered,

gravitational potential energy at the released point and the kinetic energy of the 3 runs of thecart

b. GRAPHS

Figure 1. Position versus Time of the 3 runs

Figure 2. Minimum and maximum positions of the 3 runs


8/15

Figure 3.Velocity versus Time of the 3 runs

Figure 4. Slope of the first run

Figure 5. Slope of the second run


9/15

Figure 6. Slope of the third run

Figure 7. Slope of the 3 runs

Figure 8. Maximum positions of the 3 runs


10/15

c. CALCULATIONS

c.1 Final Velocity

Vf = Vi + a * t

where:

Vf = final velocityVi = initial velocity

t = change in time

a = acceleration

c.2 Gravitational Potential energy

Ug =mgh

where:m = mass

g = gravityh = heaight/vertical distance

c.3 Kinetic Energy

KE = mv 2

where:

KE= Kinetic energy

m = mass

v = velocity

c.4 Acceleration

a= v

t

where:

v = change in velocityt = change in time


11/15

V. ANALYSISBase on Table 4, the third run of the cart has the greatest kinetic energy at the lowest

point and gravitational potential energy at the released point. This is due to the factthat the ramps height in this run is highest among the 3 runs.

It is also noticeable that as the height increases, the final velocity also increases. But

it is the opposite when it comes to the distance covered-it decreases as the heightincreases.

In terms of value of the 2 energies, as the gravitational potential energy of the 3 runsincreases, their kinetic energy also increases.

VI. CONCLUSION

While at the top of the ramp, the cart has a large quantity of potential energy and hasno kinetic energy. As the cart descends, its potential energy is transformed to kinetic

energy as it speeds up. Potential energy is converted to kinetic energy as motion

takes place, then, as motion decreases, kinetic energy is again converted to potential

energy. Even though there is an absence of external forces while doing work, the

total mechanical energy is conserved.

Initial potential energy is equal to the final kinetic energy. Both the GPE and KE are

directly proportional to the height of the ramp.

VII. ANSWERS TO QUESTIONS1. What kind of energy did the cart have at its release point?

At its release point the cart has a large quantity of potential energy and basically no kinetic

energy, while it is almost at rest.

2. How did the cart obtain that energy?

The cart can obtain and conserve energy if and only if conservative forces are doing work on the

cart.


12/15

3. What kind of energy/energies did the cart have as it was rolling down the ramp?

As the cart rolls down the ramp, its potential energy is transformed into kinetic energy and the

car speeds up.

4. What happens to the velocity of the cart as it slides down the incline plane? How doesthis affect the kinetic energy of the cart? How about its potential energy?

As the cart descends the incline plane, it gains speed. The stored energy (potential energy) fromthe release point will be transformed to its minimum amount, while the low moving energy

(kinetic energy) is transformed to its maximum amount as the cart loses height.

5. As the height of the ramp increases, what happened to the

a. Acceleration of the cartThe acceleration of the cart also increases.

b. Initial potential energy of the cartInitial potential energy would reach its maximum level.

c. Final kinetic energy of the cartIt would also reach its maximum level, thus making it equal to the initial potentialenergy.

6. As the mass of the cart increases, what happened to the

a. Acceleration of the cartAcceleration would decrease since the more something weighs, or the more mass it has,

the more acceleration or force is required to move it.

b. Initial potential energy of the cartInitial potential energy would increase and will reach its maximum level.

c. Final kinetic energy of the cartIt would be at the same maximum value level of the initial potential energy of the cart


13/15

7. Based from your data, what is the initial mechanical energy and the final mechanical

energy of the cart? How do the values of the initial mechanical energy and final

mechanical compare to the initial potential energy and final kinetic energy?

The initial mechanical and the final mechanical energy of the cart are of the same values-their

maximum levels.

8. How does this experiment demonstrate the transformation of Mechanical energy?

It shows that at the start the pushcart possesses only PE. As it moves down, it loses PE and

gains KE, but the sum of KE and PE remains constant. When it reaches the ground, it loses

all the PE but has the maximum KE (PE lost=KE gained).

VIII. REFERENCES1. Williams, Trinklein, Metcalfe.Modern Physics, 1

stedition.1984

2. Cordero-Navaza and Valdes.Physics, 2nd

edition. 20013. Hewitt. Conceptual Physics. 2005


14/15


15/15

Documents

Experiment 2 by Bayot, Lim, Uy