Cepheid variable Essays

  • The Lady of Luminosity: Henrietta Swan Leavitt

    1178 Words  | 3 Pages

    as Henrietta Swan Leavitt challenged these notions of female inferiority and ineptitude by entering the predominately male field of astrology and excelling. Henrietta Leavitt's prodigious discovery of the period-luminosity relationship amongst Cepheid variable stars would forever change the way we perceive the universe and known galaxies as well as lay the foundation for astronomers such as Harlow Shapley, Hertzsprung, and Edwin Hubble to expand our knowledge of the universe. The androcentric view

  • The Effect Of Voltage On A Current Through A Filament Lamp Lab Report

    866 Words  | 2 Pages

    · Variable Resistor. · Ammeter. · Voltmeter. · 6V Filament Lamp. · 7 Wires. Definitions: Ammeter - This is a device that measures the current of electrons in Amps. It has to be placed in Series on the circuit. Voltmeter - This is a device for measuring the potential difference of the electrons in the circuit. They are measured in Volts. It is placed in Parallel. Variable Resistor - This acts in the same way

  • Heart Rate Lab Report

    998 Words  | 2 Pages

    exercise are on the heart rate. And to record these results in various formats. VARIABLES: - * Type of exercise * Duration of exercise * Intensity of exercise * Stage of respiration * Age of the person exercising * level of fitness and recovery rate * gender of candidate * temperature * amount of recovery time KEY VARIABLE: - The variable that I will be using is the duration of exercise, this is because it is easy to measure

  • How Length And Width Of Copper Wire Affect The Current

    1172 Words  | 3 Pages

    Circuit Task: To investigate how length and width of copper wire affect on the current of a circuit. Prediction: In this experiment, the input variable will be changing the length of the copper wire used in the experiment, and also the SWG of the wire, which means the width of the wire. By changing this variable, the current the circuit will vary. With my knowledge in science and some research on the factors that affect a circuit's resistance. I am able to

  • Investigating The Internal Resistance Of A Lemon Battery

    1656 Words  | 4 Pages

    Internal Resistance Investigation I will conduct the following investigation with the aim to find the internal resistance of a lemon battery, which I will construct myself. The variables that could affect my experiment are as follows: · Size of lemon - I will conduct my experiment in no longer than an hour, allowing me to use the same lemon for all results · Size of metal electrodes - I will use the exact same electrodes throughout the whole experiment ·

  • Philosophy of the Pseudoabsolute

    3130 Words  | 7 Pages

    gnoseological sense the fundamental feature of the absolute is unambiguity. The absolute is unambiguous, it has always and everywhere only one meaning. Relative is, on the contrary, conditional, it exists only in reference to other beings; it is variable, unstable, it changes in various relations. That is the ontological status of the relative, which in gnoseological language means ambiguity, it has multimeaning. Relative is ambiguous. One of the most difficult problems of philosophy is the investigation

  • Differences in Absentees in the Workplace between Smokers and Non-smokers

    807 Words  | 2 Pages

    counterparts. Does the smoker miss more work than the non-smoker? Data from these random samples were used to draw a conclusion…. SMOKERSDATA **VERSUS**DEFINITION NON-SMOKERSTABLE Unit of Observation: Smoking and Non-Smoking Employees Variable Name:       Definition:       Unit of Measurement:       Data Source: Smoker       Employee      Days Absent in Past Year       http://lad.org/issues/4/horizon.html; Smokes             July 11, 2000 Non-Smoker       Employee Does      Days

  • Rates of Reaction

    3005 Words  | 7 Pages

    the speed of the rate of reaction when reacting with Magnesium Ribbon. I want to find out whether the strength of Hydrochloric acid will affect the speed of the rate of reaction when reacting with Magnesium Ribbon. Variables There are two important independent variables in my investigation the first of which is the concentration of the Hydrochloric Acid used during the investigation. The concentration of the acid will partly determine how fast the reaction takes place, if we put some

  • Investigate the factors affecting the rate of Osmosis

    1562 Words  | 4 Pages

    as a higher temperature would mean diffusion would occur quicker. The mass and surface area of the potatoes at the beginning of the experiment are other controls I will need to monitor to ensure a fair test. The mass of the potato is a dependent variable; this means that it will be measured throughout the experiment. I will measure the mass in grams correct to 2d.p. The potato chip will be measured before it is put in the solution, and after. This will allow us to see whether osmosis has taken place

  • How Osmosis Affects A Potato Chip

    1364 Words  | 3 Pages

    increase. I predict that the weight of the potato in the sugar solution will decrease when it reaches 3:1 (salt: water). In put Variables: -Molarity -Size of potato -Mass of Water -Molarity of Sugar -Length of time in the solution -Temperature of water Out put variables: -Weight of potato Key variables: -Molarity of sugar. This is a key variable because it has the most effective outcome because osmosis only works when there are different molarities in and outside of the potato

  • Nonexperimental Research Essay

    1168 Words  | 3 Pages

    Vocabulary Assignment #1 Nonexperimental Research (McMillan, 2012, p.13): Nonexperimental research is a quantitative research design in which the researcher has no control over any of the variables or factors within a study, and thus cannot influence the behavior of the subjects of the study. This phrase relates to a study that I may conduct because I would like to investigate how student-athletes’ academic achievement compares to that of non-student-athletes. In such an investigation, I would

  • The Effect of Exercise on Heart Rate

    736 Words  | 2 Pages

    blood is needed to run in the circulatory system, therefore the heart rate will go up. Variables: The results can be affected by the following things, the change of amount of exercises, the change of time for exercising and resting, the change of temperature and the change of person and their health. Input variables: The input variable will be the time of exercises. Output variables: The output variable will be the results of heart rate. Fair test: To make this experiment a fair test

  • An Investigation To Show How the Voltage Affects the Current In a Light Bulb

    758 Words  | 2 Pages

    so if you put more lamps into the circuit there is more resistance. As the resistance of the variable resistor decreases the current in the circuit increases until the bulbs burn out. If the number of bulbs in a series circuit is increased, less current will flow. The lamps resist the current, so if you put more lamps into the circuit there is more resistance. As the resistance of the variable resistor decreases the current in the circuit increases until the bulb burns out. The filament

  • Osmosis

    1066 Words  | 3 Pages

    Osmosis is the passage of water from a region of high water concentration through a semi-permeable membrane to a region of low water concentration. The aim of the investigation is to find the variables that affect the rate of osmosis and how they affect the rate of reaction. The variables that affect the rate of reaction of osmosis are, · The surface area of the object, · The concentration of the solution, · Temperature of the experiment Surface area If the surface area

  • Surface Area's Effect on the Way Enzymes Work

    1203 Words  | 3 Pages

    works. Catalase is a biological catalyst which means that is speeds up a reaction itself. I am going to see how much foam is created after 5 minutes, this should show us whether the amount of surface gives a better or worse reaction. My input variable will be the surface area. The potato which contains the Catalase will be cut into piece this size: 1cm x 1cm x 2cm. Test tube A will have a piece of potato which is this size. Test tube B will have this size potato in but cut in half and

  • The Reaction of Sodium Thiosulphate with Hydrochloric Acid

    614 Words  | 2 Pages

    [IMAGE] Seconds ------- There are five factors, which affect the rate of a reaction, they are: 1. Temperature 2. Concentration 3. Pressure 4. Surface Area 5. Catalyst Therefore the independent variable will be the temperature, the dependant variable will be the time, and the control will be me. I Have decided to investigate what effect temperature has on the rate of reaction, because it is the most practical to do, and it doesn't take a lot of time. Whenever I am

  • Investigating the Amount of Oxygen Given Off When Catalase Reacts with Hydrogen Peroxide

    1230 Words  | 3 Pages

    such as potato and liver. It's used for removing Hydrogen Peroxide from cells. Hydrogen Peroxide is the poisonous product of metabolism. Catalase speeds up the decomposition of Hydrogen Peroxide into oxygen and water. Variables I will make sure I keep the following variables the same. Size of potato: The Size of a potato cube would effect the investigation because the size of the cube would effect the number of cells in contact with the hydrogen peroxide. Temperature: Temperature can

  • The Loading of a Cantilever

    852 Words  | 2 Pages

    slowly when they are on. The clamp used to fasten the ruler to the table will be sufficiently tight to hold the ruler with no danger of it slipping or moving, (yet not so tight that it could damage the table.) Variables Independent Variable: Mass on ruler Dependent Variable: Depression of ruler I have kept the distance that the ruler is from the edge of the table constant, (95cm is over the edge of the table.) I have not altered the set up of the apparatus throughout the experiment

  • Resistance of a Wire

    2329 Words  | 5 Pages

    wire is made from to see whether it affects the resistance, and seeing whether the variable resistor also affects the wire in any way. Apparatus * Power pack * 9 strands of copper wire, 0.193 mm thick, 30 cm long. * 9 strands of nichrone wire, 0.193 mm thick, 30 cm long. * 9 strands of constantan wire, 0.193 mm thick, 30 cm long. * Ammeter, 10 amps max. * Voltmeter, 20 volts max. * Variable resister * Heat proof matt. * 7 wire leads. * 2 crocodile clips. * Ruler

  • How the Resistance of a Filament Bulb Varies Its Current Flowing through It

    662 Words  | 2 Pages

    more. If the voltage increases the bulb will shine bright because the bulb would have more energy. Controlled Variable- the controlled variable for this experiment is number of bulbs because the decision is for me to make. Independent Variable- the independent variable for this experiment are the volts, I will be using 1-12v. Independent Variable- The independent variable would be the reading we get of the ammeter. Apparatus- * 5 wires * 1 filament bulb * 1 resister *