I NEED HELP PLEASE, THANKS! :)
Explain how the diffraction of light shows that light behaves like a wave.

Answer:

Cloth:

It is an insulator since it can't let electricity pass through

Dry Wood:

It is an insulator and can't conduct electricity.

Tap Water:

It is a good conductor as it contains dissolved salts.

Glass:

It is an insulator since it can't let electricity pass through.

Answer:

The substances which allow an electric current to pass through it is called conductors.

Example: Metals like copper,iron ,graphite etc.

The substances which do not allow the electric current to pass through is called Insulators.

Example: Glass, dry wood ,plastic etc.

Hope this helps...

Good luck on your assignment...

Answer:

1960 J

Explanation:

EK = (18 kg + 62 kg)[tex](7.0 m/s)^{2}[/tex]/2 = 1960 J

Answer: mg/Cosθ

Explanation:

Taking horizontal acceleration of wedge as 'a'

FCosΘ = FsinΘ

F = mass(m) × acceleration(a) = ma

For horizontal resolution g = 0

Therefore,

Horizontal = Vertical

maCosΘ = mgSinΘ

aCosΘ = gSinΘ

a = gSinΘ/CosΘ

Recall from trigonometry :

SinΘ/Cosθ = tanΘ

Therefore,

a = gtanΘ

Normal force acing on the wedge:

mgCosΘ + maSinΘ - - - - (y)

Substitute a = gtanΘ into (y)

mgCosΘ + mgtanΘsinΘ

tanΘ = sinΘ/cosΘ

mgCosΘ + mgsinΘ/cosΘsinΘ

mgCosΘ + mgsin^2Θ/cosΘ

Factorizing

mg(Cosθ + sin^2Θ/cosΘ)

Taking the L. C. M

mg[(Cos^2θ + sin^2Θ) /Cosθ]

Recall: Cos^2θ + sin^2Θ = 1

mg[ 1 /Cosθ]

mg/Cosθ

Answer: There will be 75258 nuclei left at 6 pm.

Explanation:

a) half-life of the radioactive substance:

Half life is the amount of time taken by a radioactive material to decay to half of its original value.

[tex]t_{\frac{1}{2}}=\frac{0.69}{k}[/tex]

[tex]k=\frac{0.69}{t_{\frac{1}{2}}}=\frac{0.693}{2hours}=0.346hours^{-1}[/tex]

b) Expression for rate law for first order kinetics is given by:

[tex]A=A_0e^{-kt}[/tex]

where,

k = rate constant  

t = time for decomposition = 6 hours ( from 12 noon to 6 pm)

A = activity at time t = ?

[tex]A_0[/tex] = initial activity  = 600, 000

[tex]A=600000\times e^{-0.346\times 6}[/tex]

[tex]A=75258[/tex]

Thus there will be 75258 nuclei left at 6 pm.

Explanation:

The angle of incidence is always smaller than the angle of refraction

Answer:

There must be an equal amount of each element on both sides of the equation. Hope this helps and please marks as the brainliest.

Explanation:

Answer:

The answer is D

Explanation:

Hope this helps!

Answer:

  The acceleration would double

Explanation:

Assuming the same box and spring, the maximum acceleration is proportional to amplitude. When the amplitude doubles, the acceleration would double.

__

A spring is generally considered to have a linear force vs. distance characteristic. Hence, doubling the distance doubles the force. The acceleration is proportional to the force.

Answer:

  (vix, viy) = (14.7 m/s, 10.3 m/s)

Explanation:

The velocities of interest are ...

  (vix, viy) = (vi)(cos(35°), sin(35°)) = (18 m/s)(cos(35°), sin(35°))

  (vix, viy) = (14.7 m/s, 10.3 m/s)

Answer:

First one = 14.7

Second one = 10.3

Explanation:

EDGE

Answer:

The most of the elements in the periodic table are metals. The elements cannot be gases and liquids (Molecules are mainly gases and liquids). Metalloids are few. Examples (Germanium, Arsenic)

Answer:

[tex]I=0.5 \:A[/tex]  is the correct answer.

Explanation:

Using the ohm's law, we have:

[tex]V=IR\\\\I=\frac{V}{R}=\frac{3}{6}\\\\I=0.5 \:A[/tex]

Best Regards!

Answer:

elements in the same periodic table group have the same valence electrons

Answer:

  500 m

Explanation:

The applicable relation is ...

  wavelength = speed/frequency

  wavelength = (5000 m/s)/(10 cycles/s) = 500 m/cycle

The wavelength is 500 meters.

Answer:

First we use the fact that the ratio of the voltage on the secondary and on the primary will be the same as the ratio of the number of turns of both coils,

u=u^2/U^1 = N^2/N^1

we evaluate the unkown secondary voltage

u^ 2=N^2/N^1 u1

We substitute the given values -

u^2= 10/500 * 120v = 2.4v

Hence, the answer is 2.4v.

​

Answer:

So the weight of the body is 700N

Explanation:

mass of the object=70kg

force of gravity=10N/kg

weight of the object=w-?

as we know that

weight=mass × force of gravity

weight=70kg × 10N/kg

WEIGHT OF THE BODY=700N

I HOPE IT WILL HELP YOU

GOOD LUCK FOR THE ASSIGNMENT

The correct answer is 700 N.

Object mass = 70 kg

Gravity = 10N / kg

Weight = Mass x Gravity

Weight = 70kg x 10N / kg

Weight = 700 N

Mass is more basic because it is a unique property of the object. Weight varies from place to place depending on the acceleration of gravity. If the mass on the earth is m = 10kg, the weight is W = mg = 10 x 10 = 100N.

The strength of the Earth's gravitational field is 10 Newtons (N / kg) per kilogram. This means that there is a force of 10 Newtons per kilogram on Earth. Mass is the amount of substance that makes up an object.

Learn more about gravitational strength here: https://brainly.com/question/25624188

#SPJ2

Answer:

How you treat someone who may have been poisoned depends on:

The person's symptoms

The person's age

Whether you know the type and amount of the substance that caused poisoning

If you are concerned about possible poisoning, call Poison Help at 800-222-1222 in the United States or your regional poison control center. Poison control centers are excellent resources for poisoning information and, in many situations, may advise that in-home observation is all that's needed.

Answer: A rolling ball eventually slows down and comes to a stop.

Explanation: Right on Edge2020, not C or B or D.

Answer:

A

Explanation:

Person above me might be right

Answer:

They are the physical parts of a computer.

examples :monitor,keyboard,system unit and mouse.

Wood is a natural insulator due to air pockets within its cellular structure, which means that it is 15 times better than masonry, 400 times better than steel, and 1,770 times better than aluminum. In addition, lightweight wood framing methods allow easy installation of additional fibre or foil insulation. i hope this is better

Answer:

The reason is because the pressure of the air inside the room drops with time which makes opening the door to require an increased amount of force to make up for the reduced pressure inside the room

Explanation:

From the kinetic theory of gases we have the following relation;

[tex]v_{rms} = \sqrt{\dfrac{3 \cdot K \cdot T}{m} }[/tex]

[tex]p = \dfrac{n \cdot MW \cdot v^2_{rms} }{3 \cdot V}[/tex]

Where:

K = Boltzmann constant

T = Temperature

m = Mass

MW = Molecular weight

V = Volume

[tex]v_{rms}[/tex] = Root mean square velocity

Whereby the room door is closed, the kinetic energy of the air particles will be used up such that the average velocity of the particles will decrease, given that the volume of the room is constant, the pressure inside the room will drop below the original pressure outside the room such that the force on the door due to the outside pressure is larger than the force on the door from inside the room requiring a larger amount of force to overcome the resistance of the now higher outside pressure force.

Answer:

a 1.26 km b 10.5 m/s

Explanation:

A. Distance travelled by the schooterist

Since the schooterist travels in a circular path, the distance moved is the circumference of a circle, C with radius r = 0.2 km

C = 2πr

= 2π(0.2 km)

= 1.26 km

So, the distance travelled by the schooterist is 1.26 km

B. The velocity of the schooterist

The velocity of the schooterist v = distance travelled/time

distance travelled = 1.26 km = 1260 m

time = 2 minutes = 2 × 60 s = 120 s

So, V = 1260 m/120 s

= 10.5 m/s

So, the velocity of the schooterist is 10.5 m/s

Answer: B

V = 7576 m/s

Explanation: Given that the

circular radius R = 7,000,000 m,

The acceleration due to Earth's gravity is 8.2 m/s2

Let's use gravitational field strength formula to get the mass of the satellite.

g = Gm/R^2

Where G = 6.674×10^−11m3⋅kg−1⋅s−2

Substitutes all the parameters into the formula

8.2 = (6.674×10^-11 × M)/(7000000)^2

Cross multiply

4.018 × 10^14 = 6.674×10^−11M

Make M the subject of formula

M = 4.018 × 10^14 ÷ 6.674×10^−11

M = 6.02 × 10^24 kg

The Force of attraction experienced by the satellite will be

F = mg

F = 6.02 × 10^24 × 8.2

F = 4.94 × 10^25 N

But centripetal force is

F = MV^2/ R

Where V = velocity of the satellite

Substitute F, M and R into the formula

4.94×10^25 = (6.02×10^24V^2)/ 7 ×10^6

Cross multiply

3.46 × 10^32 = 6.02×10^24V^2

Make V^2 the subject of formula

V^2 = 3.46×10^32 ÷ 6.02×10^24

V^2 = 57403600.2

Find the square root of the value to get V

V = 7576 m/s

The required velocity of the satellite is 7576 m/s approximately

Answer:

i = -12.7 cm; h =  5.07 cm

Explanation:

1. Find the focal length

The focal length of a concave spherical mirror is half of its radius of curvature.

f = ½r = ½ × 34.0 cm = 17.0 cm

2. Find the image distance

A convex mirror produces a virtual image behind the mirror, so the image distance is negative.

[tex]\begin{array}{rcl}\dfrac{1}{o} + \dfrac{1 }{i} & = & \dfrac{1}{f}\\\\\dfrac{1}{50.0} + \dfrac{1 }{i} & = & \dfrac{1}{-17.0}\\\\\dfrac{1}{i} & = & \dfrac{1}{-17.0} - \dfrac{1}{50.0}\\\\& = & \dfrac{50.0 - (-17.0)}{500\times(-17.0)}\\\\& = & \dfrac{67.0}{-850}\\\\i & = & \dfrac{-850}{67.0}\\\\& = & \textbf{-12.7 cm}\\\end{array}[/tex]

3. Find the image size

[tex]\begin{array}{rcl}\\\\\dfrac{h_{\text{i}}}{ h_{\text{o}}} & = & -\dfrac{i}{o} \\\\\dfrac{h_{\text{i}}}{ 20.0} & = & -\dfrac{-12.7}{50.0} \\\\h_{\text{i}} & = & 20.0 \times \dfrac{12.7}{50.0}\\\\& = & \textbf{5.07 cm}\\\end{array}[/tex]

Answer:

a. All the laboratory equipment given are very basic equipment used in all the laboratories. Name of each equipment is as follows:

b. Use of each laboratory equipment identified is:

Answer:

(a) 4.82 m/s

(b) The simmer need to head 57.05° upstream of the river to reach a point directly opposite the river

(c) 4.024 seconds

Explanation:

The parameters given are;

The speed of the swimmer = 5.75 m/s

The direction of the resultant motion = 40° downstream

The speed of the current = x m/s

Therefore in a given second, we have that the swimmer moves 5.75 meters across the river while the current moves x meters downstream

Which gives;

[tex]tan(40^{\circ}) = \dfrac{x}{5.75}[/tex]

x = 5.75 × tan(40°) = 4.82 m/s

The speed of the current = 4.82 m/s

(b) If the swimmer swims at a direction θ to reach a point, p, directly opposite the river, we have;

The resultant speed across the river will be the swimmer's swimming speed which is 5.75 m/s

5.75² = y² + 4.82²

y = √(5.75² - 4.82²) = √9.78

tan(θ) = 4.82/(√9.78) = 1.54

θ = tan⁻¹(1.54) = 57.05°

The simmer need to swim 57.05° upstream to reach a point directly opposite the river

(c) If the river is 15 m wide, we have;

Time (t) = Distance/speed

The component of the swimmer's speed directly across the river = 5.75/(tan(57.05°)

The component of the swimmer's speed directly across the river = 3.73 m/s

The time, t, to cross the river is therefore;

t = 15/3.73 = 4.024 seconds

Answer:

Explanation:

ave speed is always (frequency) x (wavelength)

Speed  =  (450 /sec) x (0.52 m)

=      234 m/sec .

Note that the correct times are t = 0, t = 1/4, t = 1/2. You can tell from the spaces between the two digits. i.e 1&4 and 1&2

Answer:

y(0) = 2.00 cm

y(1/4) = 1.56 cm

y(1/2) = 1.21 cm

Explanation:

This is a very simple exercise, the displacement of the oscillating weight from equilibrium has already been modeled by the equation:

[tex]y(t) = 2e^{-t} cos 4t[/tex]

Where y = displacement ( in cm)

and t = time (in seconds)

The task is to find the displacement when t = 0, 1/4 and 1/2

When t = 0 s

[tex]y(0) = 2e^{0} cos 4(0)\\y(0) = 2* 1*1\\y(0) = 2.00 cm[/tex]

When t = 1/4 s

[tex]y(1/4) = 2e^{-1/4} cos 4(1/4)\\y(14) = 2e^{-1/4} cos (1)\\y(1/4) = 1.56 cm[/tex]

When t = 1/2

[tex]y(1/2) = 2e^{-1/2} cos 4(1/2)\\y(14) = 2e^{-1/2} cos (2)\\y(1/2) = 1.21 cm[/tex]

Answer: If i'm not mistaken I think it A) potential