Answer:
a) a = 3.72 m / s², b) a = -18.75 m / s²
Explanation:
a) Let's use kinematics to find the acceleration before the collision
v = v₀ + at
as part of rest the v₀ = 0
a = v / t
Let's reduce the magnitudes to the SI system
v = 115 km / h (1000 m / 1km) (1h / 3600s)
v = 31.94 m / s
v₂ = 60 km / h = 16.66 m / s
l
et's calculate
a = 31.94 / 8.58
a = 3.72 m / s²
b) For the operational average during the collision let's use the relationship between momentum and momentum
I = Δp
F Δt = m v_f - m v₀
F = 
F = m [16.66 - 31.94] / 0.815
F = m (-18.75)
Having the force let's use Newton's second law
F = m a
-18.75 m = m a
a = -18.75 m / s²
<span>31.3 m/s
Since the water balloon is being launched at a 45 degree angle, the horizontal and vertical speeds will be identical. Also the time the balloon takes to reach its peak altitude will match the time it takes to fall. So let's create a few expressions about what we know.
Distance the water balloon travels at velocity v for time t
d = vt
Total time required for the entire trip is double since the balloon goes up, then goes down
t = 2v/a
Now let's plug in the numbers we have, assuming the acceleration due to gravity is 9.8 m/s^2
t = 2v/9.8
100 = vt
Substitute 2v/9.8 for t in the 2nd formula
100 = v(2v/9.8)
Solve for v.
100 = v(2v/9.8)
100 = 2v^2/9.8
980. = 2v^2
490 = v^2
22.13594 = v
So we now know that both the horizontal velocity and vertical velocity needed is 22.13594 m/s. Let's verify that
2*22.13594 / 9.8 = 4.51754
So it will take 4.51754 second for the balloon to hit the ground after being launched.
4.51754 * 22.13594 = 100
And during that time it will travel 100 meters horizontally.
But we need to know the total velocity. And the Pythagorean theorem comes to the rescue. Just square the 2 velocities, add them together, and take the square root. We already know the square is 490 from the work above, so
sqrt(490+490) = sqrt(980) = 31.30495 m/s</span>
Answer:
Explanation:
A pure substance is something that is entirely made up of particles that are identical to each other.
Any substance that is not pure, must be a mixture.
We are surrounded by mixtures. The air is a mixture of gases . The oceans are a mixture of (mainly) water and salt. The solid earth is mostly rock, which is a mixture of different minerals.
Natural resources are substances we need and use, which occur naturally. Some come from living things, (example) cotton other are non-living (example) sand.
The opposite of a natural resource is a made resource.
The ice cubes were floating in water because they are less dense than liquid water. When water is frozen, a structure that is crystalline is formed that is held by hydrogen bonding. Due to the orientation of these bonds, the moleules would push far away from each other causing it to have a bigger volume and a lower density.
Answer: 91.94 kg
Explanation: Supoose Al's mass is m. The combined mass is 168kg, so Jo's mass is 168 - m.
The Law of Conservation of Momentum states that when two objects collide, the total momentum of both objects before the collision is the same as the total momentum of both objects after the collision.
At the beginning, Al and Jo are united without movement, so their initial momentum is zero.
After the release of their hands, Al goes in one direction and Jo moves to the opposite direction. Suppose the direction Al is moving is positive. Conservation of momentum will be
where
index i referes to initial momentum
index f to final momentum
index 1 refers to Al
index 2 to Jo
Calculating:
![m(0.91)-[(168-m)(1.1)]=0](https://tex.z-dn.net/?f=m%280.91%29-%5B%28168-m%29%281.1%29%5D%3D0)
m = 91.94
Al has a mass of 91.94 kg.
