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1. Ships – steel which is used to make ships is 6-7 times dense than water but a ship is able to float on water because it is designed to displace more water than its volume. Load lines called plimsoll marks are marked on the side to indicate the maximum load at different seasons to avoid overloading.
2. Submarines – they are made of steel and consists of ballast tanks which contain water when they have to sink and filled with air when they have to float. This makes the submarines to balance their weight and be able to rise upwards.
3. Balloons – when they are filled with helium gas balloons become lighter and the upthrust on the balloon becomes greater than their weight therefore becoming able to rise upwards.
4. Hydrometers – they are used to measure the relative densities of liquids quickly and conveniently. Various types of hydrometers are made to measure different ranges of different densities i.e. lactometer – for measuring milk water (range 1.015 – 1.045), battery acid tester – used to test the charge in a lead-acid battery.
Mutiso answered the question on October 16, 2018 at 07:08
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