All categories

3 years ago

For an object to appear red, what must happen?

Physics

1 answer:

Lapatulllka [165]3 years ago

3 0

Answer:

<h2><em><u>C. It must reflect red light wavel</u></em></h2>

Explanation:

<em>The color of the object is reflected by the object other colors are absorbed by the object.</em>

Here <em>object appears in red color so red color is reflected by the object and other colors are absorbed.</em>

You might be interested in

In 8,450 seconds, the number of radioactive nuclei decreases to 1/16 of the number present initially. What is the half-life (in

almond37 [142]

Answer:

<h2>2113 seconds</h2>

Explanation:

The general decay equation is given as $N = N_0e^{-\lambda t} \\\\$ , then;

$\dfrac{N}{N_0} = e^{-\lambda t} \\$ where;

$N/N_0$ is the fraction of the radioactive substance present = 1/16

$\lambda$ is the decay constant

t is the time taken for decay to occur = 8,450s

Before we can find the half life of the material, we need to get the decay constant first.

Substituting the given values into the formula above, we will have;

$\frac{1}{16} = e^{-\lambda(8450)} \\\\Taking\ ln\ of \both \ sides\\\\ln(\frac{1}{16} ) = ln(e^{-\lambda(8450)}) \\\\\\ln (\frac{1}{16} ) = -8450 \lambda\\\\\lambda = \frac{-2.7726}{-8450}\\ \\\lambda = 0.000328$

Half life f the material is expressed as $t_{1/2} = \frac{0.693}{\lambda}$

$t_{1/2} = \frac{0.693}{0.000328}$

$t_{1/2} = 2,112.8 secs$

Hence, the half life of the material is approximately 2113 seconds

7 0

3 years ago

An electric hoist is used to lift a 235.0 kg load to a height of 69.0 m in 38.1 s. (a) what is the power of the hoist in kw?

Ugo [173]

$Given:\\m=235.0kg\\h=69.0m\\t=38.1s\\g=9.81 \frac{m}{s^2} \\\\Find:\\P=?\\\\Solution:\\\\P= \frac{W}{t}\\\\W=\Delta E_p\\\\E_p_0=0\Rightarrow \Delta E_p=E_p\\\\E_p=mgh \\\\P= \frac{mgh}{t} \\\\P= \frac{235kg\cdot9.81 \frac{m}{s^2}\cdot69m}{38.1s} \approx 4175W=4.175kW$

4 0

3 years ago

Energy is observed in two basic forms: potential and kinetic. Which of the following correctly matches these forms with a source

Travka [436]

Answer:

option C

Explanation:

The correct answer is option C

Kinetic energy is the energy which is due to the motion of body.

Potential energy is the energy due to virtue of position of the object.

option A is not true because potential energy is due the position of the body

Option B should be the potential energy not kinetic energy.;

Option D is motion of individual molecule leads to kinetic energy not potential energy.

So, the correct answer is option is the covalent bonds of a sugar molecule is potential energy because of the position of bond.

4 0

3 years ago

How does increased pressure result in the formation of a mineral?

drek231 [11]

The best answer is
A) <span>The atoms in the mineral get rearranged

Over time, and under great pressure, the atoms of a substance can become rearranged, forming a new substance. For example, the intense pressure that carbon underground experiences, perhaps in the form of coal, can rearrange the atoms of the substance to create a diamond. </span>

5 0

4 years ago

A toy train is pushed forward and released at Xi = 4.0 m with a speed of 2.5 m/s. It rolls at a steady speed for 2.0 s, then one

Fittoniya [83]

I don't think that 4m has anything to do with the problem. anyway. here. A___________________B_______C where A is the point that the train was released. B is where the wheel started to stick C is where it stopped From A to B, v=2.5m/s, it takes 2s to go A to B so t=2 AB= v*t = 2.5 * 2 = 5m The train comes to a stop 7.7 m from the point at which it was released so AC=7.7m then BC= AC-AB = 7.7-5 = 2.7m now consider BC v^2=u^2+2as where u is initial speed, in this case is 2.5m/s v is final speed, train stop at C so final speed=0, so v=0 a is acceleration s is displacement, which is BC=2.7m substitute all the number into equation, we have 0^2 = 2.5^2 + 2*a*2.7 0 = 6.25 + 5.4a a = -6.25/5.4 = -1.157 so acceleration is -1.157m/(s^2)

8 0

3 years ago

Read 2 more answers