Answer:
I think it's D!!
cuz protons are in the atoms
Answer:
(a)
(b)
Explanation:
According to the law of conservation of momentum:
Initially, the girl and the plank are at rest. So, relative to the ice, we have:
(a) The velocity of the girl relative to the ice is:
Here, is the velocity of the girl relative to the plank and is the velocity of the plank relative to the ice.
Replacing (1) in (2):
(b) According to (2), the velocity of the plank relative to the surface of ice is:
The negative sing indicates that the plank is moving to the left.
weight = mg acts
downwards <span>
normal force = N acts upwards.
and force F acts at an angle θ below the horizontal.
(Let us assume that the woman pushes from the left, so F is
acted towards the right, which is below the horizontal)
so that, Frictional force, f=us*N acts towards the left
Now we balance the forces along x and y directions:
y direction: N = mg + F sinΘ
x direction: us * N = F cosΘ
We let the value of µs be equal to a value such that any F
will not be able to move the crate. Then, if we increase F by an amount F',
then the force pushing the crate towards the right also increases by F' cosΘ. Additionally,
the frictional force f must raise by exactly this amount.
Since f can’t exceed us*N, so the normal force must increase
by F' cosΘ/us.
Also, from the y direction equation, the normal force exceeds
by F' sin Θ.
<span>These two values must be the same, therefore:
<span>us = cot θ</span></span></span>
Answer: A
Explanation:Earthquakes occur on faults - strike-slip earthquakes occur on strike-slip faults, normal earthquakes occur on normal faults, and thrust earthquakes occur on thrust or reverse faults. When an earthquake occurs on one of these faults, the rock on one side of the fault slips with respect to the other.
Answer:
Digestion helps mammals eliminate bodily waste.
Explanation:
Humans are considered mammals and we use digestion to eliminate bodily waste. Digestion has three main functions. First digestion of food, second absorption of nutrients, and third elimination of solid waste. There are two processes that take place Mechanical digestion and chemical digestion. Mechanical digestion is the chewing and breaking down of food into smaller molecules, whereas chemical digestion is the breakdown of the smaller molecules into simpler nutrients that the body can absorb and use.