Answer:
A: 1.962
B: 3.924
Explanation:
g = G *M /R^2
g = 9.807*M/R^2 the gravitational constant of ground level on earth is about 9.807
g = 9.807*5lbs/R^2 the average brick is about 5 pounds.
g = 9.807*5*10^2. I'm assuming the height is around ten feet to help you out.
with these numbers plugged in you get an acceleration of 0.4905 a final velocity after 4 seconds 1.962. It's height fallen after 4 seconds is 3.924.
( M = whatever the brick weighs it's not specified in the question)
(R = the distance from the ground or how high the scaffold is)
(hopefully you can just plug your numbers in there hope this helps)
The second statement is the correct choice. Don't make me type it out.
Quartz, gold and calcite are examples of minerals, coal is a fossil fuel
Answer: Image for option 4
Explanation:
The fourth option is correct because there are three forces acting on the block:
which is the <u>Friction force</u> and acts against the movement of the block
the <u>Normal Force</u>, which is perpendicular (normal) to the surface of the rough ramp
the Weight of the block, which is the force due gravity acceleration and has an <em>x-component</em> and an <em>y-component.</em>
Answer:
A. Underground coal mining is dangerous because of possible tunnel collapse and possible methane gas explosions.
Explanation:
Dangers of underground coal mining include asphyxiation, methane gas poisoning, tunnel collapse and explosions of methane gas, a highly flammable gas. Methane explosions occur since this gas is a byproduct of coal. This explosion can cause tunnel collapse.