Franklin had been waiting for an opportunity like this. He wanted to demonstrate the electrical nature of lightning, and to do so, he needed a thunderstorm.
He had his materials at the ready: a simple kite made with a large silk handkerchief, a hemp string, and a silk string. He also had a house key, a Leyden jar (a device that could store an electrical charge for later use), and a sharp length of wire. His son William assisted him.
Franklin had originally planned to conduct the experiment atop a Philadelphia church spire, according to his contemporary, British scientist Joseph Priestley (who, incidentally, is credited with discovering oxygen), but he changed his plans when he realized he could achieve the same goal by using a kite.
Answer: water freezes inside a rock, causing it to break
Weathering is a natural process in which the rocks break into pieces or sediments by the action of wind, water and chemical agents. Frost wedging is a physical weathering process. It occurs in an area where temperature fluctuations occurs due to change in the climatic conditions. This occurs due to rapid heating and cooling. The rocks lying in a cold environment, the water residing in the rocks gets freezed. The water in ice form that is solid form acquire more space than in liquid form, therefore, the developed ice will affect the physical structure of the rock. The formation of ice results in the development of break or crack in the rock typically in the shape of a wedge and thus the phenomena is called as frost wedging.
Hence, frost wedging happens when water freezes inside a rock, causing it to break.
Answer:
The correct answer is oxygen and hydrogen
We know that
• The mass of the elevator is 5000 kg.
Let's draw a free-body diagram.
As you can observe, there are just two forces involved, the weight of the elevator and the tension force. Let's use Newton's Second Law.
But, W = mg = 5000kg*9.8m/s^2 = 49,000 N, and m = 5000 kg, a = 0 (because the speed is constant).
<h2>Therefore, the tension in the cable is 49,000 N.</h2>
