Friction between our feet and the surface we walk on is desirable. True False

Who sponsored Felix Baumgartner in the second space jump that took placed in 2008?

KengaRu [80]

Alban Geissler, who developed the SKYRAY carbon fiber wing with Christoph Aarns, suggested after Baumgartner's jump that the wing he used was a copy of two prototype SKYRAY wings sold to Red Bull (Baumgartner's sponsor) two years earlier. - wiki

8 0

2 years ago

You stand17.5 m from a wall holding a baseball. You throw the baseball at the wall at an angle of 20.5∘ from the ground with an

Lelechka [254]

Answer: 8.8 m

Explanation:

The movement of the baseball to the wall is a example of parabolic motion. While the baseball aproach the wall it is affected by gravity.

In this case, because the Initial Velocity of the ball is a vecotr, it can be defined using its two directionals compounds. One, on the Y-axis and another on the X-axis. This can be related, on how a hypotenuse is the product of two legs of the triangle. Because of this, each one of this, can be know using the following equation:

Vx = Vo * cos(∅)

Vy = Vo * sin(∅)

Where Vo is the initial velocity 27.5 m/s, and ∅ is the angle which is 20.5°. So we calculate:

Vx = 27.5m/s * cos(20.5)

Vx = 27.5m/s * 0.936

Vx = 25.74m/s

Vy = 27.5m/s * sin(20.5)

Vy = 9.62m/s

Now the movement is divided on two parts, one under the effect of gravity and another one with a constant velocity.

To know how tall does the baseball hit the wall, we need to know first how much time it takes the ball to reach the wall on the X-axis. The wall is 17.5m away, we velocity on Vx that is constant we can calculate as it follow:

Time (T) = Distance (D) / Velocity (V)

Where Distance is 17.5m and our Velocity is the Vx calculated before.

T = 17.5 m / 25.74m/s

T = 0.68s

This is the time it takes the ball to reach the wall.

Know with the time, we can calculate the how tall it got on that time with the following equation:

$x = (Vo*t) + (\frac{1}{2} *a*t^{2} )$

Where Vo is the Y-Compound of the Initial Velocity.

a is the aceleration, in this case the Gravity. Which, will be negative because is oposing the movement. Gravity is equal to 9.81 $m/s^{2}$

And t is the time it takes the ball to get to the wall.

$x = (Vy*T) + (\frac{1}{2} *g*T^{2} )$

$x = ((9.62m/s)*0.68s) + (\frac{1}{2} *(9.81m/s^{2})*(0.68s)^{2} )$

$x = 8.8 m$

This is the height that the baseball touch the wall.

6 0

3 years ago

How many leptons are in ⁷₃Li?

shutvik [7]

-- Electrons are leptons. There are three electrons in each neutral Lithium atom.

The last two parts of the question are absurd.

-- Bonbons are candy, not atomic particles. A bonbon cannot fit into a Lithium atom.

-- A pentagon is a closed geometric figure that has five sides. Although you could, in principle, have a pentagon small enough to fit into a Lithium atom, you could never find a piece of paper small enough to draw it on.

5 0

3 years ago

suppose a child walks from the outer edge of a rotating Merry-Go-Round to the inside does angular velocity of the Merry-Go-Round

Akimi4 [234]

Okay here initially child walks on the outer edge of the disc and then started to move inside

So here as the child and Merry go round is an isolated system so there is no external Torque on this system from outside

As here we can see there is external force acting on this system by the hinge of the Merry go round as well as due to gravity so we can not use momentum conservation to solve such type of questions.

But as we can say that there is no external torque on this system about the hinge point so we will use conservation of angular momentum for this system

Here as we know that

$\tau = \frac{dL}{dt}$

where L = angular momentum

since here torque is ZERO

$0 = \frac{dL}{dt}$

L = constant

so here we can write initial angular momentum of the system as

$L = (I_1 + I_2)*\omega$

here we know that

$I_1$ = moment of inertia of merry go round

$I_2$ = moment of inertia of child

so here we can say

$(I_1 + I_2)* \omega_1 = (I_1 + I_2')\omega_2$

so here as the child moves from edge to inside the disc it moment of inertia will decrease because as we know that moment of inertia of child is given as

$I_2 = mr^2$

here m = mass of child

r = distance of child from center

Since child is moving inside so his distance from center is decreasing

so here moment of inertia of child is decreasing as he starts moving inside

so final angular speed of merry go round will increase as child go inside

$\omega_2 = \frac{(I_1 + I_2)*\omega}{(I_1 + I_2')}$

so here as

$I_2' < I_2$

final angular speed will be more than initial speed as child moves inside

3 0

2 years ago

A molecule of methane gas is shown. What do the red and blue dots represent? A) Protons being shared between the atoms. B) Elect

nalin [4]

Thank you for posting your question here at brainly. I hope the answer will help you. Feel free to ask more questions.

The red and blue dots represent is

Protons being shared between the atoms. The answer is A>

7 0

3 years ago

Friction between our feet and the surface we walk on is desirable. True False​

Friction between our feet and the surface we walk on is desirable. True False