Over time, the types of technology can vary and be improved upon so that more advanced techniques become more valued. This could be the situation with mining whereby back in the 1500's in underground mines the rock was broken by fire setting ie lighting a fire below the rock face to heat up the rock and then throwing cold water on it to crack it, so that it could be dug by hand. With the advent of explosives, this all changed so that the rock could be blasted. The increase in advance rates for an underground heading have thus gone from 5-20 feet per month to up to 300meters (984 ft) per month for a 24/7 mining operation, which is a huge improvement.
Answer:
<em>Velocity is the rate at which the position changes</em>
<em>Velocity is the rate at which the position changesWhy do we need</em>
<em>Velocity is the rate at which the position changesWhy do we needVectors make it convenient to handle quantities going in different directions</em><em>.</em><em>.</em><em> </em>
Explanation:
Thank you!
Answer:
10.4mm
Explanation:
2 pages = 1 leaf
200 pages = 100 leaves
100 × 0.10 = 10 mm thickness
Total thickness = 2(0.20) +10 = 0.4+10 = 10.4mm
Work done = force * distance
work done = 200 * 20
work done = 4000J
Mirrors reflect meaning shows what would be seen if everything was turned around, therefore, it shows text backwards because if it is turned around, it is in reverse order.