Zadanie 28
Wzorowane na: Chemistry SL Paper 1, November 2022, pytanie 28. Treść, dane i kontekst są zmienione; sprawdzane umiejętności, format i punktacja jak w oryginale.
Darmowe konto pozwoli wrócić do niego później.
Polecenie
A student weighs a sample of solid on a balance several times and gets slightly different readings each time. A check with a standard 100.00 g mass shows that the balance always reads 0.30 g too high. Which pair of actions best reduces the effect of the random error and of the systematic error, respectively?
A. Random error: calibrate against a standard mass; systematic error: repeat the readings and calculate the mean
B. Random error: repeat the readings and calculate the mean; systematic error: repeat the readings and calculate the mean
C. Random error: repeat the readings and calculate the mean; systematic error: use a balance that displays more decimal places
D. Random error: repeat the readings and calculate the mean; systematic error: calibrate against a standard mass
Sprawdź rozwiązanieUkryj rozwiązanieKlucz i punktacja
Odpowiedź z klucza
D ✔
«random errors scatter the readings in both directions, so averaging repeated readings reduces their effect. A systematic error shifts every reading in the same direction and is not removed by averaging or by more decimal places; it is corrected by calibrating the instrument against a known standard»
Schemat punktowania
One mark for the correct option.