Alysha wants to test the effect of different materials on the melting rate of ice. She finds the initial mass of four pieces of ice. She then covers three pieces with either tinfoil, plastic wrap, or paper. The fourth piece is left uncovered.After 30 minutes, Alysha calculates the final mass of each piece of ice to determine which melted the fastest.What are the independent and dependent variables in Alysha's experiment?

. A company has made a new material called ‘Wellwarm’. They want to use ‘Wellwarm’ to make coats. (a) A scientist tested ‘Wellwarm’ to see how well it insulated a beaker of hot water. She tested ‘Wellwarm’ and three other materials as shown below. She wrapped each beaker in a different material. She recorded the temperature at the start and 20 minutes later. (i) What was the independent variable that the scientist changed? (ii) What was the dependent variable that the scientist measured during the investigation? (b) The results of the investigation are shown below. time (minutes) temperature of water (°C) wrapped in material A material B material C material D 0 60 60 60 60 20 34 40 38 36 material A material B material C material D thermometerlidPrimaryTools.co.ukPrimaryTools.co.uk KS3/09/Sc/Tier 3–6/P1 19 Total 8 9c 1 mark 9bii 1 mark 9c 1 mark 9d 1 mark 9e 1 mark (i) The scientist said that the ‘Wellwarm’ material is the best insulator. Which material was ‘Wellwarm’? Use the results to help you. Tick the correct box. (ii) Use the evidence in the results table to explain your choice. (c) The company made a coat from each of the four materials they tested. A person tested the different coats by wearing each one in a cold room. He measured the temperature inside each coat for 30 minutes. Write down two other variables that should be controlled to make this a fair test. 1. 2. (d) Write down one thing the scientists should do to make sure the person testing the coats is safe. (e) Suggest one advantage of using a temperature sensor and data logger instead of a thermometer in this experiment. maximum 8 marks 9bi 1 mark

Which of the following is the dependent variable?A. TimeB. Purity of waterC. Amount of Alka-SeltzerD. Temperature

Write down what the independent and dependent variables are in this experiment.

Scenario 1A chef is trying to figure out if adding salt to the top of their lasagna will change how fast cheese melts.They put four lasagnas, with different amounts of salt, into the oven at 180ºC. They then timed how long the cheese took to melt on each lasagna.Question 8SavedIdentify the independent variable.Amount of saltOven temperatureTime to melt the cheeseType of cheeseI'm not sureQuestion 9SavedIdentify the dependent variable.Amount of saltOven temperatureTime to melt the cheeseType of cheeseI'm not sureQuestion 10SavedDetermine a testable hypothesis for this investigation.Scenario 2You are setting up an investigation to answer the following testable question:Does the water temperature affect the time it takes to boil an egg?Question 11Identify the independent and dependent variables. Independent variableDependent variableQuestion 12SavedDetermine a testable hypothesis for this investigation.Question 13Identify two controlled variables and explain why they need to remain the same.Controlled variableReason for control

Determine why the ice melted on the aluminium plate faster than on the plastic plate.