Please need help with this

What is most important when selecting the right pfd for a passenger on board your boat?

Karolina [17]

The most essential while choosing the privilege PFD for a traveler is the information required for choosing right PFD for the traveler's body weight and trunk size.Note that the offspring of what age under 8 years old are required to wear legitimately secured PFD while on vessel unless in securely closed cabin.

3 0

3 years ago

Read 2 more answers

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

Suppose you are at the center of a large freely-rotating horizontal turntable in a carnival funhouse. As you crawl toward the ed

I am Lyosha [343]

Answer:

c. remains the same, but the RPMs decrease.

Explanation:

Because there aren't external torques on the system composed by the person and the turntable it follows that total angular momentum (I) is conserved, that means the total angular momentum is a constant:

$\overrightarrow{L}=constant$

The total angular momentum is the sum of the individual angular momenta, in our case we should sum the angular momentum of the turntable and the angular momentum of a point mass respect the center of the turntable (the person)

$\overrightarrow{L_{turnatble}}+\overrightarrow{L_{person}}=constant$ (1)

The angular momentum of the turntable is:

$\overrightarrow{L_{turnatble}}=I\overrightarrow{\omega}$ (2)

with I the moment of inertia and ω the angular velocity.

The angular momentum of the person respects the center of the turntable is:

$\overrightarrow{L_{person}}=\overrightarrow{r}\times m\overrightarrow{v}$ (3)

with r the position of the person respects the center of the turntable, m the mass of the person and v the linear velocity

Using the fact $v=\omega r$ :

$\overrightarrow{L_{person}}=\overrightarrow{r}\times rm\overrightarrow{\omega}$ (3)

By (3) and (2) on (1) and working only the magnitudes (it's all that we need for this problem):

$I\omega+r^{2}m\omega=constant$

$\omega(I+r^{2}m)=constant$

Because the equality should be maintained, if we increase the distance between the person and the center of the turntable (r), the angular velocity should decrease to maintain the same constant value because I and m are constants, so the RPM's (unit of angular velocity) are going to decrease.

4 0

4 years ago

A 750-kg automobile is moving at 26.2 m/s at a height of 5.00 m above the bottom of a hill when it runs out of gasoline. The car

Kisachek [45]

To solve this problem it is necessary to apply to the concepts related to energy conservation. For this purpose we will consider potential energy and kinetic energy as the energies linked to the body. The final kinetic energy is null since everything is converted into potential energy, therefore

Potential Energy can be defined as,

$PE = mgh$