Who among the following built a model steam engine in 1698 called "Miner's Friend" to drain mines ?
- A.Thomas Savery
- B.Thomas Newcomen
- C.James Watt
- D.Richard Arkwright
Correct answer
Explanation
The correct answer is A, Thomas Savery. The English engineer Thomas Savery patented a steam pump in 1698 and called it the Miner's Friend, as it was meant to pump water out of flooded mines.
Savery's machine had no piston. Steam was let into a vessel and then cooled, and the vacuum it left sucked water up from below; fresh steam pressure then pushed the water higher. It worked only in shallow mines, used a great deal of fuel and its boilers were liable to burst. Even so, it was the first practical use of steam power and opened the way for the steam engines that drove the Industrial Revolution.
B is wrong because Thomas Newcomen built his atmospheric engine with a piston in 1712. C is wrong because James Watt improved Newcomen's engine with a separate condenser in 1769. D is wrong because Richard Arkwright is known for the water frame for spinning cotton in 1769, not for a steam engine.
Exam tip: steam engine sequence is Savery 1698, Newcomen 1712 and Watt 1769.
Practice Questions
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- B.10 Ω
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