Science Homework #22: Year 11

Science Homework #22:  Year 11

Homework    Topic:
Question 1 Give two sources from which salt ca be extracted. C3
Question 2 Open-label, blind and double blind are types of human trials- which is least open to bias? B2
Question 3 A simple name for an object emitting radiation is a __________?? P2
Question 4 The absorption/ reflection of infra-red radiation by gases in the atmosphere when it is given out by the Earth causes the Earth's temperature to (increase/ stay the same/ decrease). P2
Question 5 Which type of cells remember the antigens of micro organisms, allowing immunity? B2
Question 6 Two numbers are given for a blood pressure reading- what is happening to the heart for the lower value? B2
Question 7 1000J of energy is put into a motor and we get 850J of useful movement out of the motor. What is the efficiency of the motor? P3
Question 8 Which two types of radiation can optical fibres carry? P2