All categories

4 years ago

Which of the following would likely be the best reflector of heat energy

1 answer:

4 0

If these are the missing choices:
<span>A. gritty navy blue surface.
B. bumpy red surface.
C. dull orange surface.
D. Polished pale yellow surface.

My answer: D. Polished pale yellow surface

I read an article that summarized the results of the emission of radiation experiments. It stated the following:
1) </span>Black surfaces are the best emitters of heat radiation.
2) Black surfaces are the best absorbers of heat radiation.
3) Shiny surfaces are the best reflectors of heat radiation.
4) Shiny surfaces are poor absorbers of heat radiation.
<span>5) Glass will not transmit long wave infra red radiation.

Because of the above summary, that is why I arrived at the answer D. Polished pale yellow surface would likely be the best reflector of heat energy.</span>

You might be interested in

How do mass and force affect the acceleration of an object?

joja [24]

Gravity affects weight, it does not affect mass. Masses always remain the same. Newton's Second Law of Motion: Force = mass x acceleration The acceleration of an object is: a) directly proportional to the net force acting on the object. ... c) inversely proportional to the mass of the object.

3 0

4 years ago

Read 2 more answers

Four objects are situated along the y axis as follows: a 2.09-kg object is at +2.97 m, a 2.93-kg object is at +2.53 m, a 2.57-kg

Tcecarenko [31]

Answer:

x = 0 m

y = 1.02 m

Explanation:

M1 = 2.09 kg

y1 = 2.97 m

M2 = 2.93 kg

y2 = 2.53 m

M3 = 2.57 kg

y3 = 0 m

M4 = 3.92 kg

y5 = -0.496 m

since all objects are situated on the Y-axis, this means the x coordinate of the center of mass is 0.

To find the y coordinate of the center of mass, we apply the equation below.

sum of moment of the objects about the origin = moment of the total mass of objects about the center of mass

M1.y1 + M2.y2 + M3.y3 + M4.y4 = Mt.Y

(2.09 x 2.97) + (2.93 x 2.53) + (2.57 x 0) + (3.92 x -0.496) = (2.09 + 2.93 + 2.57 + 3.92) Y

11.68 = 11.51 Y

Y = 11.68 / 11.51 = 1.02 m

7 0

3 years ago

A builder drops a brick from a height of 15 m above the ground. The gravitational field strength g is 10 N/ kg. What is the spee

Basile [38]

The speed of the brick dropped by the builder as it hits the ground is 17.32m/s.

Given the data in the question;

Since the brick was initially at rest before it was dropped,

Initial Velocity; $u = 0$

Height from which it has dropped; $h = 15m$

Gravitational field strength; $g = 10N/kg = 10 \frac{kg.m/s^2}{kg} = 10m/s^2$

Final speed of brick as it hits the ground; $v = \ ?$

<h3>Velocity</h3>

velocity is simply the same as the speed at which a particle or object moves. It is the rate of change of position of an object or particle with respect to time. As expressed in the Third Equation of Motion:

$v^2 = u^2 + 2gh$

Where v is final velocity, u is initial velocity, h is its height or distance from ground and g is gravitational field strength.

To determine the speed of the brick as it hits the ground, we substitute our giving values into the expression above.

$v^2 = u^2 + 2gh\\\\v^2 = 0 + ( 2\ *\ 10m/s^2\ *\ 15m)\\\\v^2 = 300m^2/s^2\\\\v = \sqrt{300m^2/s^2}\\ \\v = 17.32m/s$

Therefore, the speed of the brick dropped by the builder as it hits the ground is 17.32m/s.

Learn more about equations of motion: brainly.com/question/18486505

8 0

2 years ago

A transformer has a primary coil with 375 turns of wire and a secondary coil with 1,875 turns. An AC voltage source connected ac

Sonbull [250]

Answer:

The rms voltage (in V) measured across the secondary coil is 459.62 V

Explanation:

Given;

number of turns in the primary coil, Np = 375 turns

number of turns in the secondary coil, Ns = 1875 turns

peak voltage across the primary coil, Ep = 130 V

peak voltage across the secondary coil, Es = ?

$\frac{N_P}{N_s} = \frac{E_p}{E_s} \\\\E_s = \frac{N_sE_p}{N_p} \\\\E_s = \frac{1875*130}{375} \\\\E_s = 650 \ V$

The rms voltage (in V) measured across the secondary coil is calculated as;

$V_{rms} = \frac{V_0}{\sqrt{2} } = \frac{E_s}{\sqrt{2} } \\\\V_{rms} = \frac{650}{\sqrt{2} } = 459.62 \ V$

Therefore, the rms voltage (in V) measured across the secondary coil is 459.62 V

7 0

3 years ago

Armand hands the rock to Pierre, who is standing next to the trampoline. Explain how Armand moves, in terms of the forces acting

Nikolay [14]

Answer:

Armando's weight ,restored force created by the trampoline

a harmonic movement within the trampoline

Explanation:

In a trampoline we have two forces that actuate Armando's weight and the restored force created by the trampoline that depends on the deformation distance of the elastic canvas.

Amando's weight is vertical and directed towards the center of the Earth and has a constant value, this weight is balanced with the elastic force the springboard exerts on Armando in a vertical direction.

In general, when entering the trampoline, a small jump is made, this creates a speed that deforms the canvas until the speed is reduced to zero, at this point the elastic force is greater than the weight and the boy begins to climb, After the boy leaves the canvas he meets only the force of gravity and his speed decreases to zero and begins his fall.

In Summary Armando is in a harmonic movement within the trampoline

6 0

3 years ago