Answer:Orient your line of sight directly above the measurement markings.
Explanation: parallax error is a type of systematic error that occurs when an observer views a measurement marking at a wrong angle. This causes a noticeable disparity in results obtained. Therefore the best way to prevent this error is to view and record the data from the correct angle. This can be obtained by:
-Place the measurement device on its edge so it is level with the object being measured.
-Seek out the finest possible edge of the measurement device, or use a device with finer edges.
In conclusion, ask other observers to also take the reading and get an average of their results. It can help cancel out parallax error results.
Answer:
The spring constant = 9.25 N/m
Explanation:
The equation of an object attached to a spring that is oscillating is
T = 2π√(m/k)
Where T = period of the oscillation, m = mass of the object, k = spring constant.
Making k the subject of the equation,
k = 4π²m/T²......................... Equation 1
Note: Period(T) is the time taken to complete one oscillation
Given: T = t/10 = 9.0/10 = 0.9 s, m = 190 g = 0.19 kg.
Constant: π = 3.14
Substitute these values into equation 1.
k = 4(3.14)²(0.19)/0.9²
k = 7.4933/0.81
k = 9.25 N/m
Thus the spring constant = 9.25 N/m
The chemical change occurred. Electrolysis is used by scientists to make chemical reactions that wouldnt normaly spontaniously ocur. In this case we are getting new gases from water molecul which is change in structure of elements ( we are getting new moleculs)