Compare and contrast what happens to an object's motion when balanced or

What happens when a spinning ice skater draws in her outstretched arms? Group of answer choices Her moment of inertia increases

kotegsom [21]

Answer:

Her moment of inertia decreases causing her spin to speed up. The physics law behind this phenomenon is the conservation of angular momentum.

Explanation:

<em>Theory</em>

<u>The Law of conservation of angular momentum</u>

The angular momentum of a rotating body or a system remains constant unless it is acted upon by an external unbalance force.

Angular momentum = moment of inertia × angular velocity

The moment of inertia = mass×[perpendicular distance from axis of rotation]²

___________________________________________________________

⇒When skater draws in her outstretched arms the mass distribution get concentrated towards the axis of rotation so the moment of inertia of the body decrease.

But angular moment should conserve so angular velocity increases (spin increases)

5 0

3 years ago

Water pressure in a lake is greater __________. a. at the bottom b. at the surface c. at any point, for pressure is the same d.

sweet-ann [11.9K]

Answer:

The correct answer a

Explanation:

In the fluid pressure is a measure of force per unit area, in this case force is the weight of the fluid that increases as we descend. Therefore, the pressure increases with the depth of the fluid.

The correct answer a

7 0

3 years ago

Read 2 more answers

Which sport requires the least amount of agility? HELLLLPPP

ZanzabumX [31]

Answer:

golf

Explanation:

it's less physical strength in more of you hitting the ball with whatever the stick is called

5 0

3 years ago

A circular loop of flexible iron wire has an initial circumference of 165.0cm, but its circumference is decreasing at a constant

djverab [1.8K]

Answer:

0.005 V

Explanation:

We are given that

Initial circumference of circular loop=C=165 cm

Rate of circumference, $\frac{dC}{dt}=12 cm/s$

Magnetic field,B=0.5 T

We have to find the induced emf at time t=9 s

We know that induced amf,E= $\frac{Bd(A)}{dt}$

Area of circular coil,A= $\pi r^2$

$E=B\frac{d(\pi r^2)}{dt}=B(2\pi r)\frac{dr}{dt}$

Circumference of circular coil,C= $2\pi r$

$165=2\pi r$

$r=\frac{165}{2\pi}$

$\frac{dr}{dt}=\frac{1}{2\pi}\frac{dC}{dt}=\frac{1}{2\pi}\times (12)=\frac{6}{\pi} cm/s=\frac{6\times 10^{-2}}{\pi} m/s$

Radius of coil at time t=9 s

$r=\frac{165}{2\pi}-(\frac{6}{\pi}\times 9)=9.08 cm=9.08\times 10^{-2} m$

$1 m=100 cm$

E= $-0.5(2\pi\times 9.08\times 10^{-2})\times \frac{6\times 10^{-2}}{\pi}=-0.005 V$

Magnitude of induced emf=0.005 V

4 0

3 years ago

Read 2 more answers

________ cable is NOT subject to electromagnetic interference or radio frequency interference. Polycarbonate Twisted-pair Coaxia

malfutka [58]

Answer:

The correct option is: d. Fiber-optic

Explanation:

A fiber-optic cables or an optical-fiber cable is a cable that is composed of a bundle of optical fibers. These cables are used for transmitting information or digital signals over long distances.

Each optical fiber in an optical-fiber cable is individually coated with a protective plastic cover and contained in a protective tube. Therefore, an optical-fiber cable is not affected by any electromagnetic interference or radio frequency interference.

5 0

3 years ago