Both analog and digital signals are used to transfer information. The table compares the features of each. Analog Digital Wave Type Signal continuous, or "curvy", changes with time individually separate, or "box-like", also known as binary Uses cassette tapes, videotapes, record players, older cameras compact disks (CDs), digital video disks (DVDs), digital photos, cell phones Power Requirement higher, because of wide range of amplitudes and frequencies lower, because only two signals (the "one" and the "zero") are transmitted Storage degrades in quality with age and re-recordings quality remains the same over time Security lower, because tapping into an analog circuit can detect signals in their original form higher, since binary systems are easier to change to a secret code—known as encryption Images courtesy of NASA 4 Select the correct answer from each drop-down menu. Based on the information in the table, what type of signal is being transmitted and received in the image below? graph of transmitted signal in red and received signal in blue; the amplitude of the received signal is higher in some places and lower in others than the amplitude of the transmitted signal The image shows transmission of signal because there is of the transmitted signal. Transferring information using this type of signal requires .

How is energy related to the change of state represented by the model? atoms gain energy as a solid changes to a liquid. atoms gain energy as a solid changes to a gas. atoms lose energy as a solid changes to a liquid. atoms lose energy as a solid changes to a gas.

Show transcript transcripts online experiment: atomic structure [the history of atomic theory] this animation will you test rutherford’s hypothesis that it took a great number of shots to actually hit the nucleus because the size of the atom was so much larger than the nucleus.[clipboard and pencil with a diagram of rutherford’s gold foil experiment] we are going to use a cardboard box to represent the atom, a wooden block to represent the nucleus, and marbles to represent the alpha particles. [animated cardboard box, wooden block, and marbles] the box’s measurements are: length = 50 cm, width = 25 cm, and height = 25 cm. the measurements of the block are: length = 10 cm, width = 10 cm, and height is 5 cm. jose and priscilla will conduct the experiment. [animated boy and girl] priscilla put the block in the box on the floor. jose will close his eyes and drop marbles into the box trying to hit the block. priscilla will count the number of times the marbles hit the block and move the block in the box after each hit. [animated block moving inside the box. marble dropping into the box.] here is priscilla’s data of how many times the marble hit the block. out of 100 marble drops or shots, the marble hit the block 32 times. [data table: first column: marble, with rows 1 to 100; column 2: hit, with rows indicating yes or no. last row: total hits] now you can follow the directions in the experiment to present your findings. present your findings when you are finished with the experiment, complete the following data analysis and record your answers in the essay box below. determine the volume of the box and the block. determine the ratio of the block to the box: multiply this number by 100 to turn it into a percent. complete this statement: the volume of the block is percent of the volume of the box. determine the ratio of the number of hits to the number of shots: multiply this number by 100 to turn it into a percent. complete this statement: the block was hit percent of the time. compare the results of step 2 to the results of step 3. are the percentages similar? write a conclusion discussing the following items: based on your findings, do you think rutherford's hypothesis was reasonable? restate rutherford's hypothesis and describe how you tested it. state whether your results support the hypothesis. if they do not, can you suggest some error in experimental procedure (other than general human error) that might explain it? finally, explain how this experiment confirms the nuclear model of the atom and the idea that most of the atom is empty space.

What if it is did darwin used to support his theory of evolution