Learning intention- today’s measurement rotation will see you using both analogue and digital scales. You will compare the accuracy of both scales by weighing your sample of sand. The language you will use today includes- mass, weight, accuracy, increments, grams, kilograms, analogue, digital, mode.
Which scales give the most accurate reading?
Draw your own analogue scale to 1kg.
What increments did you use?
Photograph your own ‘analogue scale’ drawn with care onto the paper circle. Your scale will go to 1kg.
Photograph your sand weight on both the digital and analogue- compare your readings. Which reading is more accurate?
When do measurements matter? Discuss with your partner a time when it may be ‘critical’ to have an accurate reading.
Solve this problem. One set of our scales is not working properly. The needle will not return to zero. It can only be turned back to 200g. If 200g is your starting point, how much does a sand sample actually weigh if the reading is 675g?
Problem 2- You take your dog to the vet for a check up. The vet tells you to weigh your dog on the digital scales. Unfortunately your dog will not stand still long enough to get a reading? What will you do?