For the first one, trees are organisms, so it’s B.
The second one,, the heavy percolation and strong winds come from hurricanes. So it’s hurricanes
-- Change the battery to one with higher voltage.
-- Wrap more turns of wire around the spike.
-- If the spike is made of anything else but iron, replace it with a pure iron one.
As we know that here gun + bullet system is isolated from all other external force system
so here the momentum of system is always conserved
so we will say
here we know that
now we will have
by solving above equation we will have
To solve this problem, we must imagine that Jim’s initial
position, the position of the rock, and Jim’s final position all connects to
form a triangle. Now we can imagine that the triangle is a right triangle with
the 90° angle on the initial position.
The angle of 30° is directly opposite to the length of his
total stride while the width of the river is the side adjacent to the angle.
Therefore can use the tan function to solve for the width of the river:
tan θ = opposite side / adjacent side
tan 30 = total stride distance / width of river
where total stride distance = 65 * 0.8 = 52 m
width of river = 52 m / tan 30
<span>width of river = 90.07 m</span>
Question: Two people stand facing each other at a roller-skating rink then push off each other. If the girl skater has a mass of 30 kg and moves backward at 5 m/s, what is the velocity of the boy skater if his mass is 50 kg?
Answer:
3 m/s
Explanation:
Applying,
The Law of conservation of momentum
Momentum of the girl skater = momentum of the boy skater
MV = mv...................... Equation 1
Where M = mass of the girl skater, V = velocity of the girl skater, m = mass of the boy skater, v = velocity of the boy skater
From the question, we were asked to calculate v
v = MV/m.................. Equation 1
Given: M = 30 kg, V = 5 m/s, m = 50 kg
Substitute these values into equation 1
v = (30×5)/50
v = 3 m/s
Hence the velocity of the the boy skater is 3m/s
