Answer:· A model is a description of natural phenomenon that scientists can use to make predictions. A good model is both as accurate as possible and as simple as possible, which makes it not only powerful but also easy to understand. However, no matter how good they are, models will almost always have limitations.
Explanation:
Answer:
D. Sand carried by rivers flows over and weathers the rocks.
Explanation:
The sand in the river is move because of the flow of the river and as the sand moves it grinds on the rocks in the river. This starts a process know as abrasion, in other words it means that it wheathers(grinds) against the rocks.
Answer: It's hard to say without characterizing the collision. But it will be either A if the collision is totally in-elastic, or B if the collision is totally elastic. It could be anywhere in between for partially elastic collisions.
Explanation:
momentum is conserved, so initial system momentum will be left to right.
The velocity of the center of mass is 50(5) / 550 = 0.4545... m/s
In an elastic collision, the lead ball will move off at twice that speed or 0.91 m/s to the right.
The steel ball will bounce back and move away at 0.91 - 5 = -4.1 m/s . The negative sign indicates the steel ball has reversed course and has negative momentum
In a totally in-elastic collision, both balls would move to the right at 0.45 m/s. The steel ball will still have positive momentum.
Answer:
N = 3.54 * 10²³ atoms
Explanation:
The formula to apply here is the idea gas law;
PV = nRT where ;
P= pressure of the gas= 1.013 * 10⁵ Pa
V= volume of the gas = 4/3 * 3.14 *0.15³= 0.01414 m³
n= amount of a substance = ?
R= ideal gas constant= 8.314
T= temperature= 293 K
Applying the values to the formula;
PV = nRT
1.013 * 10⁵ * 0.01414 = n * 8.314*293
n= 1.013 * 10⁵ * 0.01414 / 8.314*293
n= 0.588 moles
1 mole = 6.022 * 10²⁷ atoms/ mole
0.588 moles = 0.588 * 6.022 * 10²⁷
N = 3.54 * 10²³ atoms