Light is a form of what

023 (part 1 of 2) 10.0 points

Annette [7]

Answer:

Part 1

The angular speed is approximately 1.31947 rad/s

Part 2

The change in kinetic energy due to the movement is approximately 675.65 J

Explanation:

The given parameters are;

The rotation rate of the merry-go-round, n = 0.21 rev/s

The mass of the man on the merry-go-round = 99 kg

The distance of the point the man stands from the axis of rotation = 2.8 m

Part 1

The angular speed, ω = 2·π·n = 2·π × 0.21 rev/s ≈ 1.31947 rad/s

The angular speed is constant through out the axis of rotation

Therefore, when the man walks to a point 0 m from the center, the angular speed ≈ 1.31947 rad/s

Part 2

Given that the kinetic energy of the merry-go-round is constant, the change in kinetic energy, for a change from a radius of of the man from 2.8 m to 0 m, is given as follows;

$\Delta KE_{rotational} = \dfrac{1}{2} \cdot I \cdot \omega ^2 = \dfrac{1}{2} \cdot m \cdot v ^2$

I = m·r²

Where;

m = The mass of the man alone = 99 kg

r = The distance of the point the man stands from the axis, r = 2.8 m

v = The tangential velocity = ω/r

ω ≈ 1.31947 rad/s

Therefore, we have;

I = 99 × 2.8² = 776.16 kg·m²

$\Delta KE_{rotational}$ = 1/2 × 776.16 kg·m² × (1.31947)² ≈ 675.65 J

3 0

3 years ago

Is it true or false that A proton traveling to the right moves in between the two large plates. A vertical electric field, point

Lelu [443]

Answer:

False

Explanation:

In the question it is given that a proton travels in the right moves in between the two plates. An electric field that is pointing in the vertically upward direction has magnitude of 3 N/C. The electric field is produced by the plates.

Now from here we can conclude that the direction of the force acting on the proton when the proton is in between the plates acts in the downward direction. While the electric field lines points in the upward direction. Thus the electric point will not be in the direction of the force that acts on the proton.

3 0

3 years ago

A book is dropped from a window. It takes 5 seconds to reach the ground. What is its velocity after 2 seconds? What’s the veloci

ira [324]

Answer:

Explanation:

Initial velocity is 0. In the equation v = v0+at where v0 is the initial velocity of 0, we only have to fill in -9.8 for a and 2 for t to get the velocity after 2 seconds -19.6 m/s; after 5 seconds, when it hits the ground, a = -9.8 and t = 5 to give a velocity of -49 m/s. Gravity pulls down everything at the same rate, it doesn't matter whether we drop a feather or an elephant from the window!

3 0

3 years ago

It is estimated that there is no more than 30 grams of this element in the earth's crust at any one time.

oksano4ka [1.4K]

<span>Astatine is the limited element found in the Earth's crust. This element is the rarest one found in the crust and it is radioactive. It is named after the Greek word "astatos" which means unstable. The first acknowledgement of it, came in 1940, which was when it was declared.</span>

3 0

3 years ago

Read 2 more answers

Rubber is which of the following?

telo118 [61]

insulator.

it has no electrons free within it to move and to make an electric current

4 0

3 years ago