Ask question

Ask question

All categories

zloy xaker [14]

2 years ago

8

When all wavelengths of the visible light spectrum are present, the color is seen. _ is seen when all wavel

engths of light are absent.
a.
black, white
c.
grey, brown
b.
white, black
d.
None of the above.

1 answer:

allochka39001 [22]2 years ago

7 0

B. White and black are the answers.

You might be interested in

A 5.67-kg block of wood is attached to a spring with a spring constant of 150 N/m. The block is free to slide on a horizontal fr

nikklg [1K]

Answer:

v=0.94 m/s

Explanation:

Given that

M= 5.67 kg

k= 150 N/m

m=1 kg

μ = 0.45

The maximum acceleration of upper block can be μ g.

a= μ g ( g = 10 m/s²)

The maximum acceleration of system will ω²X.

ω = natural frequency

X=maximum displacement

For top stop slipping

μ g =ω²X

We know for spring mass system natural frequency given as

$\omega=\sqrt{\dfrac{k}{M+m}}$

By putting the values

$\omega=\sqrt{\dfrac{150}{5.67+1}}$

ω = 4.47 rad/s

μ g =ω²X

By putting the values

0.45 x 10 = 4.47² X

X = 0.2 m

From energy conservation

$\dfrac{1}{2}kX^2=\dfrac{1}{2}(m+M)v^2$

$kX^2=(m+M)v^2$

150 x 0.2²=6.67 v²

v=0.94 m/s

This is the maximum speed of system.

7 0

3 years ago

Read 2 more answers

Calculate the magnitude of the linear momentum for the following cases. (a) a proton with mass 1.67 10-27 kg, moving with a spee

abruzzese [7]

Answer:

<h2>8.0995×10^-21 kgms^-1</h2>

Explanation:

Mass of proton :

$m_P=1.67\times 10^-^2^7\:kg\\$

Speed of Proton:

$v_P=4.85\times 10^6$

Linear Momentum of a particle having mass (m) and velocity (v) :

$-> p =m->v\:\:\: (1)$

Magnitude of momentum :

$p=mv\:\:\: (2)$

Frome equation (2), magnitude of linear momentum of the proton :

$p_P=m_P\:v_P\\\\p_P=1.67\times 10^-^2^7 \:kg\times4.85\times 10^6\:ms^-^1\\\\p_P= 8.0995\times 10^-^2^1\:kgms^-^1$

7 0

2 years ago

If the resultant of two velocity vectors of equal magnitude is also of the same magnitude, then which statement must be correct?

Tamiku [17]

The correct option is C) The angle between the vectors is 120°.

Why?

We can solve the problem and find the correct option using the Law of Cosine.

Let A and B, the given two sides and R the resultant (sum),

Then,

$R=A=B$

So, using the law of cosines, we have:

$R^{2}=A^{2}+B^{2}+2ABCos(\alpha)\\ \\A^{2}=A^{2}+A^{2}+2*A*A*Cos(\alpha)\\\\0=A^{2}+2*A^{2}*Cos(\alpha)\\\\Cos(\alpha)=-\frac{A^{2}}{2*A^{2}}=-\frac{1}{2}\\\\\alpha =Cos(-\frac{1}{2})^{-1}=120\°$

Hence, we have that the angle between the vectors is 120°. The correct option is C) The angle between the vectors is 120°

Have a nice day!

4 0

3 years ago

An electron and an antielectron (positron) each have a rest energy of 0.511 MeV , or approximately 8.2×10−14 J . When an electro

Mademuasel [1]

Answer:

Explanation:

Photon is also a particle . Hence when two particles like electron and positron annihilate to get completely changed to photons , a minimum of two photons of equal and opposite momentum and energy are produced flying in opposite direction to conserve momentum and energy . Each photon will have same energy equal to 511 keV . It is so to conserve momentum and energy. Initially total momentum was zero so finally too total momentum should be zero.

8 0

3 years ago

Choose a substance you're familiar with. what are its physical and chemical properties? How would you measure its density? What

Gekata [30.6K]

<span>you can look at magnesium, it can react with oxygen to form oxides. (chemical) it is malleable and a solid at room temperature. (physical)

</span><span>to measure its density, the mass and volume can be worked out and from this density too. look up the equation, it is quite easy :)
</span><span>physical changes -- it can be melted, and oxidized

</span><span>the chemical changes of oxidation magnesium looses electrons to form oxides, this is a chemical reaction- chemical change..--- use to get the density use (rho) or density D = M/V</span>

6 0

2 years ago