In order to be accepted into college, you will more than likely need to take an entrance exam, depending on the school that you wish to attend. One entrance exam that you will need to take is the ACT exam. The ACT exam measures high-school students on what they have learned during high school and determines if they are ready to enter college-level classes. The ACT also gives you an idea as to which college-level classes you are prepared to take.
The ACT exam consists of four sections:
There is also a Writing Section on the ACT exam that is optional.
To prepare for the ACT exam, it is best to take multiple ACT practice tests to see which areas you will need more work on as well as what you can expect on the actual exam. Our ACT Science Practice is similar to those science questions you will be asked on the actual ACT exam.
The Science section of the ACT exam includes 40 questions and is timed for 35 minutes. The Science section measures the interpretation, analysis, evaluation, reasoning, and problem-solving skills that are required in the natural sciences. The Science section includes questions about:
- Interpretation of Data
- Scientific Investigation
- Evaluation of Models, Inferences, and Experimental Results
A vibrating source will produce sound by alternately forcing the air molecules in front of it closer together as it moves towards them, and then further apart as it draws away from them. In this way, alternating regions of high and low pressure, called compressions and refractions, are produced. The figure shows a typical sound wave. The volume of the sound corresponds to the magnitude of the compression, represented by the amplitude of the wave. The sound’s pitch corresponds to the wave’s frequency, the distance between successive compressions. Humans can hear sounds with frequencies between 20 and 20,000 Hertz. Sound waves propagate in all directions from their source. The speeds at which sound waves travel depend upon the medium they are traveling through. In dry air, sound travels at 330 m/sec at 0°C. It travels 4 times faster through water, and 15 times faster through a steel rod.
The sound produced by a drum is much louder and lower pitched than that produced by a bell. Which of the following statements is true about the sound wave produced by a drum compared to that produced by a bell?
a. The amplitude is greater and the wavelength is shorter.
b. The amplitude is greater and the wavelength is longer.
c. The amplitude is smaller and the wavelength is longer.
d. The amplitude is smaller and the wavelength is shorter.
B: The pitch of a sound depends upon the frequency of the sound wave. The higher the frequency, the higher the sound’s pitch. Frequency varies inversely with wavelength so that a higher pitched sound with a higher frequency will have a longer wavelength. The volume of a sound depends upon the degree to which the molecules of air (or any other medium through which the sound travels) are compressed. This compression is represented by the wave amplitude. The greater the amplitude, the louder the sound.