The sum of angles in a regular pentagon is
180*(5 - 2) = 540°
Each internal angle is 540/5 = 108°.

Each vertex creates a line of symmetry to the midpoint of the opposite side,
as shown in the figure.

Answer: 5 lines of symmetry.

7 0

3 years ago

The radius of curvature is smaller at the top than on the sides so that the downward centripetal acceleration at the top will be

kap26 [50]

Answer:

$v = 14.86 m/s$

Explanation:

As we know that the force equation at the top is given as

$\frac{mv^2}{R} = ma$

now we know that

$a_c = 1.5 g$

so we have

$\frac{v^2}{R} = 1.5 g$

$v = \sqrt{1.5 Rg}$

so we will have

$v = \sqrt{1.5(15)(9.81)}$

$v = 14.86 m/s$

3 0

3 years ago

Pilots often take advantage of the ____,which are highly-speed winds between 7km and 16 km above earths surface.

lukranit [14]

I believe it is called or referred to as the "Jet Stream". During World War II, allied pilots encountered high speed winds in the upper air. They named those winds after the fastest planes they came up against: fighters equipped with jet engines! Jet stream winds in winter time can reach up to 300 MPH as well!

6 0

3 years ago

If a rigid body rotates about point O, the sum of the moments of the external forces acting on the body about point O equals whi

Drupady [299]

Answer:

The answer to the question is A.

Explanation:

The definition of moment is Force multiplied the distance to the point of interest.

So the external moment at point O is equal to ⇒ EMо= F×d

Knowing the definition of moment of inercia (I) and a newtonian Force ( m.a)

We can say that te moment of the externals force at point O is EMо= IGa

Because the rotation of a body in a inmovil point is implicated by the moment of inercia an the action of the gravity in that moment.

6 0

4 years ago