1. Copper which is used to make electriciy wring is a very ...metal

2. High carbon steel which contains... 1.4% carbon is a ductile ... metal

3. Brass which is an ... zinc is used ... screws

4. Friction which is always present in a machine dissipates ... heat energy

5. Stairless steel contains chromium which makes ... resistant

6. Complicated mechanisms which make up ... engine are machines ... levers

7. Malleable cast iron which is ferrous is tougher than any grey cast iron

8. Steels which are vised to make tools are called tool steels

`1.` Copper which is used to make electriciy wring is a very malleable and        toughmetal

`2.` High carbon steel which contains iron and 0.7% to 1.4% carbon is a ductile tough and fairly malleable metal

`3.` Brass which is an alloy of copper and zinc is used to make bolts and screws

`4.` Friction which is always present in a machine dissipates mechanical energy by converting it into heat energy

`5.` Stairless steel contains chromium which makes the steel corrosion- resistant

`6.` Complicated mechanisms which make up an aeroplane engine are machines just as simple levers

`7.` Malleable cast iron which is ferrous is tougher than any grey cast iron

`8.` Steels which are vised to make tools are called tool steels

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