Please please help me please please help

Answer:

B

Explanation:

If you cross of what you don't think are the answers then it makes it easier to narrow it down to what the answers are.

Hope this helps!

Answer:

Density of rock piece = 2.7 g/cm³

Explanation:

Given:

Volume of rock piece = 18 cm³

Mass of rock piece = 48.6 gram

Find:

Density of rock piece

Computation:

We know relation between density, mass and volume,

Density = Mass / Volume

Density of rock piece = Mass of rock / Volume of rock

Density of rock piece = 48.6 / 18

Density of rock piece = 2.7 g/cm³

Answer:

Electromagnetic waves do not require any medium to travel whereas mechanical waves must have a medium to propagate.

So, Basically, it is B I believe.

Hope It Helps!

Answer:

3M/S

Explanation:

Answer:

The tension in string will be "3.62 N".

Explanation:

The given values are:

Length of string:

l = 3 ft

or,

 = 0.9144 m

frequency,

f = 60 Hz

Weight,

= 0.096 lb

or,

= 0.0435 kgm/s²

Now,

The mass will be:

= [tex]\frac{0.0435}{9.8}[/tex]

= [tex]0.0044 \ kg[/tex]

As we know,

⇒  [tex]\lambda=\frac{2L}{n}[/tex]

On substituting the values, we get

⇒     [tex]=\frac{2\times 0.9144}{4}[/tex]

⇒     [tex]=0.4572 \ m[/tex]

or,

⇒  [tex]v=f \lambda[/tex]

⇒      [tex]=0.4572\times 60[/tex]

⇒      [tex]=27.432 \ m/s[/tex]

Now,

⇒  [tex]v=\sqrt{\frac{T}{\mu} }[/tex]

or,

⇒  [tex]T=\frac{m}{l}\times v^2[/tex]

On putting the above given values, we get

⇒      [tex]=\frac{0.0044}{0.9144}\times (27.432)^2[/tex]

⇒      [tex]=\frac{752.51\times 0.0044}{0.9144}[/tex]

⇒      [tex]=3.62 \ N[/tex]

Answer:

Biodiversity decline continues due to a rapidly expanding human population. Habitat is damaged in order to meet growing needs for agriculture, urban development, water and materials. Fish, wildlife and plants are overharvested, despite mounting evidence that many harvesting practices are unsustainable.

Answer:

Workdone = 2940 Nm

Explanation:

Given the following data;

Force = 1470 N

Distance = 2m

Time = 5 seconds

To find the work done;

Mathematically, workdone is given by the formula;

Workdone = force * distance

Substituting into the formula, we have;

Workdone = 1470 * 2

Workdone = 2940 Nm

Answer:

Mp =Pp g    where p = density of solid Platinum

Wp  = Mp Pp g     weight of mass M

Volume displaced is 1 cm^3

Weight of water = .0098 N   since 1 cm^3 displaced

Or Ww = 1 cm^3 * .001 kg / cm^3 * 9.8 N/kg = .0098 N

Answer:

Explanation:

A cargo spacecraft was orbiting the earth. It is equipped with rocket and has an initial mass of 30 metric ton. It wants to catch up with the international space station to deliver the cargo. So its rocket engine was fired for 1 minute. The engine ejects mass at a rate of 30 kg/s with an exhaust velocity of 3.1 km/s. The pressure at the nozzle exit is 5 kPa and the diameter of exit area is 94.4 cm. What is the thrust of the eng

Answer:

M v^2 / R = centripetal force

For Red: M v^2 / R = 5 * 9^2 / 1.5 = 270

For Blue M v^2 / R = 270 = 25 * 1.8^2 / Rb

So Rb = 25 * 1.8^2 / 270 = .3 m

Answer:

Y = 0.0254 m = 25.4 mm

Explanation:

The formula for the fringe spacing in Young's Double-slit experiment is given by the following formula:

[tex]Y = \frac{\lambda L}{d}[/tex]

where,

Y = fringe spacing = 0.0176 m

λ = wavelength = 425 nm = 4.25 x 10⁻⁷ m

L = Distance between screen and slits

d = slit separation

Therefore,

[tex]\frac{0.0176\ m}{4.25\ x\ 10^{-7}\ m} = \frac{L}{d}\\\\\frac{L}{d} = 41411.76[/tex]

Now, for:

λ = 614 nm = 6.14 x 10⁻⁷ m

[tex]Y = (6.14\ x\ 10^{-7}\ m)(41411.76)\\[/tex]

Y = 0.0254 m = 25.4 mm

Answer:

Explanation:

For destructive interference , the condition is

2μt = nλ

2μt = n x 678

For constructive interference , the condition is

2μt = (2n+1)λ₁ /2

n x 678 = (2n+1)λ₁ /2

λ₁ = 1356 n / ( 2n + 1 )

λ₁ = 1356  / ( 2 + 1/n )

For longest wavelength , denominator should be smallest or n should be largest . The longest value of n is infinity so

λ₁ = 1356  /  2

= 678 nm .

Answer:

17,190 years old

Explanation:

A p e x

This question involves the concepts of kinetic energy, potential energy, and the law of conservation of energy.

The watermelon is "1.02 m" above the ground.

The total energy of the watermelon can be found by its potential energy at the highest point:

Total Energy = mgh

where,

Therefore,

Total Energy = (118 kg)(9.81 m/s²)(5 m)

Total Energy = 5787.9 J

Now, according to the law of conservation of energy, at the given point:

Total Energy = Kinetic Energy + Potential Energy

5787.9 J = 4610 J + mgh'

[tex]h'=\frac{5787.9\ J-4610\ J}{(118\ kg)(9.81\ m/s^2)}[/tex]

h' = 1.02 m

Learn more about the law of conservation of energy here:

https://brainly.com/question/2264339

Answer:

a) KE max = 3.632 * 10^{-19}

b) v = 6.31 * 10^5   m/s

c) Lambda = 195 nm

Explanation:

a) Work done is given by equation  

W = V * q = change in kinetic energy = Final KE – Initial KE

Substituting the given values, we get –  

V * 1.6*10^{-19} =0 - Initial KE

KE max = 2.27 * 1.6*10^{-19} = 3.632 * 10^{-19}

b) As we know KE = 0.5 mv^{2}

Substituting the given values, we get –  

3.632 * 10^{-19} = 0.5 * (9.11 * 10^{-31}) v^2

v = 6.31 * 10^5   m/s

c) Incident energy = W + K max

Substituting the given values we get  

hc/lambda = 4.08 * 1.6 * 10^{-19} J + 3.632 * 10^{-19} J

6.626 *10^{-34} * 3*10^8/lambda = 4.08 * 1.6 * 10^{-19} J + 3.632 * 10^{-19} J

Lambda = 1.95 * 10^7

Lambda = 195 nm

Answer:

Nuclear binding energy is the energy required to split a nucleus of an atom into its component parts: protons and neutrons, or, collectively, the nucleons. The binding energy of nuclei is always a positive number, since all nuclei require net energy to separate them into individual protons and neutrons.

I hope you find this helpful.

Wanning gibbous

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Plz mrk me brainlest

Answer:

The answer is "[tex]\bold{0, 12.8 \ \frac{m}{s^2}, and \ 6.4 \ \frac{m}{s^2}}[/tex]"

Explanation:

For point a:

The average time interval acceleration for the box [tex]t = 0\ to\ t = 250 \ s:[/tex]

[tex]\to \alpha_{0 \ to \ 2.50}=\frac{v_f - v_i}{t_f-t_i}=\frac{0-0}{2.50-0}=0[/tex]

For point b:

The average time interval acceleration for the box

[tex]t = 250 \ s\ to\ t = 750 \ s :[/tex]  

[tex]\to \alpha_{2.50 \ to \ 7.50}=\frac{v_f - v_i}{t_f-t_i}=\frac{32-(-32)}{7.50-2.50}=12.8 \ \frac{m}{s^2}[/tex]

For point c:

The average time interval acceleration for the box [tex]t = 0\ to \ t = 10 \ s :[/tex]  

[tex]\to \alpha_{2.50 \ to \ 7.50}=\frac{v_f - v_i}{t_f-t_i}=\frac{32-(-32)}{10-0}=6.4 \ \frac{m}{s^2}[/tex]

Answer:

1. effect observed when light from an object in cool air passes through warm air

→ h. total internal reflection

2. line perpendicular to a surface

→ g. normal.

3. splitting of light into its component colors angle of incidence

→ b. dispersion.

4. alignment of light into a single vibrational direction

→ i. polarization

5. larger angle as light passes from air to water

→ c. angle of incidence

6. cause of the sky's color

→ f. reflection

7. bouncing of light rays reflection

→ f. reflection

8. bending of light between media

→ j. refraction.

9. ratio of speeds of light

→ d. index of refraction.

10. inability of light to escape a low-velocity medium due to a large angle of approach refraction

→ scattering.

Answer:

D. 2,1,2,1 ​

Explanation:

The equation of the reaction is; 2AgNO3 + BeCl2 + ---------》2AgCl + Be(NO3)2

The rule applied in balancing chemical reaction equation is that the number of atoms of each element on the reactants side must be the same as the number of atoms of the same element on the products sides.

If this rule is properly applied to the reaction between silver nitrate and beryllium chloride to form silver chloride and beryllium nitrate , the coefficients in the equation are;  2,1,2,1

Answer:

1).atoms (3). mixture. (5). Element

2). particles (4). molecules (6). suspension

Explanation:

(7). Homogeneous (8). Heterogeneous

(9). compound (10). solutions

2m/s

300m+200m=500m

100s+150s=250s

500m/250s= 2m/s

The average speed of tina will be 2m/s.

We have Tina who went for a walk.

We have to determine her average speed.

Average speed is the rate of change of displacement with respect to time.

v(avg) = Δx/Δt

According to the question -

Total Distance covered = d = 500 m

Total time taken = t = 250 s

Average speed = 500/250 = 2 m/s

Hence, the average speed of tina will be 2m/s.

To solve more questions on Average speed, visit the link below-

https://brainly.com/question/22982282

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Answer:

 m₂ = 4 kg

Explanation:

The moment of inertia is defined by

         I = ∫ r² dm

for bodies with high symmetry it is tabulated, for a spherical shell

        I = 2/3 m r²

in this case the first sphere has a radius of r₁ = 2m and a mass of m₁ = 1 kg, the second sphere has a radius r₂ = 1m.

They ask what is the masses of the second spherical shell so that the moment of inertia of the two is the same.

        I₁ = ⅔ m₁ r₁²

        I₂ = ⅔ m₂ r₂²

They ask that the two moments have been equal

        I₁ = I₂

        ⅔ m₁ r₁² = ⅔ m₂ r₂²

         m₂ = (r₁ / r₂) ² m₁

let's calculate

         m₂ = (2/1) ² 1

         m₂ = 4 kg

Answer: Valid claim

Explanation:

Given

Work output is [tex]W=400\ kJ[/tex]

Work input is [tex]Q=1200\ kJ[/tex]

The temperature of the source [tex]T_h=550\ K[/tex]

The temperature of the sink is [tex]T_l=350\ K[/tex]

Efficiency is given by

[tex]\eta =\dfrac{\text{W}}{\text{Q}}\times 100[/tex]

Insert the values

[tex]\Rightarrow \eta=\dfrac{400}{1200}\times 100\\\\\Rightarrow \eta=\dfrac{100}{3}\\\\\Rightarrow \eta=33.3\%[/tex]

For ideal cycle it is

[tex]\Rightarrow \eta=\dfrac{T_h-T_l}{T_l}\times 100\\\\\Rightarrow \eta=\dfrac{550-350}{550}\times 100\\\\\Rightarrow \eta=36.36\%[/tex]

The efficiency of the cycle is less than the ideal situation, therefore, it is valid claim.

Answer:

68.9233231661

Explanation:

Just put it into your calculator, shift sin should do it but it will come up like this: [tex]sin^{-1}[/tex] which is the same as arcsin

Answer:

About 5 tons (4.96)

Answer:

Fc = 123 Newton

Explanation:

Net force can be defined as the vector sum of all the forces acting on a body or an object i.e the sum of all forces acting simultaneously on a body or an object.

Mathematically, net force is given by the formula;

[tex] Fnet = Fapp + Fg[/tex]

Where;

Fnet is the net force.

Fapp is the applied force.

Fg is the force due to gravitation.

Given the following data;

Normal force = 25N

Mass = 10kg

To find the centripetal force;

From the net force, we have the following formula;

Fc = N + mg

Where;

Fc is the centripetal force.

N is the normal force.

mg is the the weight of the object.

Substituting into the formula, we have;

Fc = 25 + 10(9.8)

Fc = 25 + 98

Fc = 123 Newton