Planning an investigation Knowledge-Based Download PDF

Questions

1. 1.

   When planning a physics investigation, why is it essential to select a measuring instrument whose resolution is substantially smaller than the expected value of the measured quantity?

   • A) To eliminate all systematic errors caused by zero offsets in the instrument
   • B) To minimize the relative or percentage uncertainty of the measured data
   • C) To prevent ambient environmental conditions from altering the control variables
   • D) To ensure that repeated measurements yield identical values without any scatter
2. 2.

   When planning a scientific investigation to determine the mathematical relationship between two continuous variables, why is it essential to choose at least six evenly spaced values for the independent variable across a wide range?

   • A) To eliminate the need for performing repeat trials at each measurement point
   • B) To ensure that random errors in the dependent variable are completely prevented
   • C) To verify that all control variables change at a steady and predictable rate
   • D) To reveal the overall pattern clearly and allow any non-linear behavior to be identified
3. 3.

   When planning an investigation to determine how the current through a resistor varies with potential difference, why is it beneficial to conduct a preliminary trial?

   • A) To establish an appropriate range and interval of values to test and identify any practical issues
   • B) To eliminate the necessity of taking repeat measurements during the main experiment
   • C) To prove that the experimental hypothesis is definitively true before gathering data
   • D) To ensure that random errors will be completely absent from subsequent readings
4. 4.

   A student is planning an investigation to determine how the length of a uniform metal wire affects its electrical resistance. Which of the following combinations of variables must be kept constant throughout the experiment to ensure a valid investigation?

   • A) Wire material, cross-sectional area, and temperature
   • B) Wire mass, applied voltage, and electric current
   • C) Wire length, volume, and applied potential difference
   • D) Wire resistance, cross-sectional area, and circuit current
5. 5.

   A student is planning an investigation to determine the period of oscillation of a simple pendulum. Which procedure should the student include in the experimental plan to reduce timing uncertainty and improve the reliability of the data?

   • A) Record the time for half of an oscillation and multiply the result by two.
   • B) Alter the length of the string after each single swing to gather varied data points rapidly.
   • C) Increase the mass of the pendulum bob continuously until timing variations disappear.
   • D) Time twenty consecutive oscillations, divide the total duration by twenty, and repeat the trial to find the mean.
6. 6.

   A student plans an investigation to determine how the release height of a ball rolling down a track affects the horizontal distance it travels after leaving the track. Which of the following procedures correctly identifies the independent variable and ensures a valid test?

   • A) Treat the horizontal distance as the independent variable while keeping the release height constant across all trials.
   • B) Vary the mass of the ball as the independent variable while changing both the release height and launch angle simultaneously.
   • C) Systematically vary the release height while altering the type of ball and surface material between trials.
   • D) Systematically vary the release height as the independent variable while keeping the ball's mass and track geometry constant.