help me with this one​

Answer:

the answer is ....angle of reflection

Answer:

7.3 g/cubic cm

Explanation:

You divide the mass by the volume to calculate the density of the metal.

146g ÷ 20cm³ = 7.3g/cm³

Answer:

Approximately 4.6 billion years ago, the solar system was a cloud of dust and gas known as a solar nebula. Gravity collapsed the material in on itself as it began to spin, forming the sun in the center of the nebula. ... Small particles drew together, bound by the force of gravity, into larger particles.

Answer:

C.

Explanation:

Force = Mass * Acceleration

So 20 = 5* Acceleration

4 = Acceleration

The acceleration of the object is 4 m/s².

To find the acceleration, the given values are:

Force = 20 N

Mass = 5 kg

Definition:

     As it was given as the values of  Force and mass, here acceleration definition depends on the Newton's second law of motion.

Using the second law of motion, the force will be equal to the product of the mass and the acceleration.

As formula,

                               F = ma Newton

Here, to find acceleration,

                              a =f/ m

Substituting the values,

                              = 20 / 5

                            a = 4m/s².

So, the acceleration was 4 m/s². The Option C is the correct answer.

Learn more about acceleration,

https://brainly.com/question/12550364

#SPJ6

Answer:

um .... D. D D D D D this should be it

There are three things needed to be classified as a planet.

Pluto meets 2 of the 3.

The one it does not meet is it doesn’t “clear the neighborhood” which means a planet needs to be gravitationally dominant over all objects around it. Meaning smaller bodies ( asteroids) would either combine with the larger body making it bigger or pushing them away ( out of their orbit) so they do not collide with the larger body.

The book's position is changing linearly with time, so its velocity is constant. This means that the net force acting on the book in the direction parallel to the surface is

∑ F = 10.0 N - n = 0

where n is the magnitude of the normal force on the book due to the wall, and the net force perpedicular to the surface is

∑ F = f - (0.550 kg) g = 0

where f is the mag. of kinetic friction, and f = µn where µ is the coefficient of kinetic friction.

Then

• n = 10.0 N

• f = (0.550 kg) g = 5.39 N

• 5.39 N = µ (10.0 N)

==>   µ = 0.539

Answer:

Above answer

Explanation:

The book's position is changing linearly with time, so its velocity is constant. This means that the net force acting on the book in the direction parallel to the surface is

∑ F = 10.0 N - n = 0

where n is the magnitude of the normal force on the book due to the wall, and the net force perpedicular to the surface is

∑ F = f - (0.550 kg) g = 0

where f is the mag. of kinetic friction, and f = µn where µ is the coefficient of kinetic friction.

Then

• n = 10.0 N

• f = (0.550 kg) g = 5.39 N

• 5.39 N = µ (10.0 N)

==>   µ = 0.539

Answer:

góc phản xạ 15°

Explanatin

Answer:

Explanation:

The direction of the applied force has to be parallel to the distance an object moved in order to say that work has been done.

Answer:

D. A

General Formulas and Concepts:

Simple Harmonic Motion

Parts of a wave

Explanation:

The amplitude is the distance from the horizon to either the crest or trough of a wave.

In layman's terms, it is how high the wave is.

The "highest" wave would be wave A.

∴ our answer is D.

Topic: AP Physics 1 Algebra-Based

Unit: SMH

Answer:

A (The wave)

Explanation:

Wave A

Answer:

[tex]{ \bf{potential \: energy = mass \times gravitation \times height}} \\ 350 = 17 \times 10 \times h \\ 350 = 170h \\ height = 2.06 \: metres[/tex]

Answer:

The height reached is 20m, The time taken to reach 20m is 2 seconds

Explanation:

Observing the equations of motion we can see that the following equation will be most helpful for this question.

[tex]v^{2} = u^{2} + 2as[/tex]

We are given initial velocity, u

We know that the stone will stop at its maximum height, so final velocity, v

Acceleration, a

And we are looking for the displacement (height reached), s

Substitute the values we are given into the equation

[tex]0^{2} = 20^{2} + 2(10)s[/tex]

Rearrange for s

[tex]0^{2} -20^{2} =20s[/tex]

[tex]-400=20s[/tex]

[tex]\frac{-400}{20} =s[/tex]

s = -20 (The negative is just showing direction, it can be ignored for now)

The height reached is 20m

Use a different equation to find the time taken

[tex]s = vt - \frac{1}{2} at^{2}[/tex]

Substitute in the values we have

[tex]-20=(0)t - \frac{1}{2} (10)t^{2}[/tex]

Rearrange for t

[tex]-20 =0 -5 t^{2}[/tex]

[tex]\frac{-20}{-5} =t^{2}[/tex]

[tex]4 = t^{2}[/tex]

t = 2s

The time taken to reach 20m is 2 seconds

Answer:

Gpe = 15680 Joules

Explanation:

Gravitational potential energy (GPE) is an energy possessed by an object or body due to its position above the earth.

Mathematically, gravitational potential energy is given by the formula;

G.P.E = mgh

Where;

G.P.E represents potential energy measured in Joules.

m represents the mass of an object.

g represents acceleration due to gravity measured in meters per seconds square.

h represents the height measured in meters.

Given the following data;

Mass = 20 kg

Height = 80 m

We know that acceleration due to gravity is equal to 9.8 m/s²

To find the gravitational potential energy;

Gpe = mgh

Gpe = 20 * 80 * 9.8

Gpe = 15680 Joules

[tex]\boxed{ \sf{Answer}} [/tex]

____________________

(a) A = 5 kgwt

B = 10 N

First convert 5 kgwt to N,

[tex]5 \times 9.8 \\ = 49 \: N[/tex]

Net force [the forces are acting in 2 opposite directions]

[tex]A - B \: \\ = 49 - 10 \\ = 39 \: N[/tex]

____________________

(b) Since, the force is greater by A ↦the block will move towards B, i.e, to the right.

____________________

(c) Frictional force will try to oppose the motion of the block but since A has greater force than B, the frictional force will be resisted.

____________________

ʰᵒᵖᵉ ⁱᵗ ʰᵉˡᵖˢ ツ

꧁❣ ʀᴀɪɴʙᴏᴡˢᵃˡᵗ2²2² ࿐

Answer:

The entropy change is 45.2 kJ/K.

Explanation:

mass of water at 100 C = 2 kg

Latent heat of vaporization, L = 2260 kJ/kg

Heat is

H = m L

H = 2 x 2260 = 4520 kJ

Entropy is given by

S = H/T = 4520/100 = 45.2 kJ/K

The entropy change during the phase change of water from liquids to steam at constant pressure and same temperatures will be zero because, Δ T is zero here.

Entropy is a thermodynamic parameter determining the measure of randomness in a system. Entropy of a natural reaction or change is always increasing.

According to second third law of thermodynamics the  entropy change of the universe is positive always. At constant pressure the entropy change a of substance of m g is written as:

ΔS = m Cp ln T2/T1.

Where Cp is the specific heat capacity at constant pressure.

Here, the initial temperature and final temperature is same 100 degree celsius. Thus T2/T1 becomes 1 and log 1 is zero. Therefore, the entropy  change in this phase change is zero.

To find more on entropy, refer here:

https://brainly.com/question/13146879

#SPJ5

Answer:

The total current in the circuit is 0.8 A.

Explanation:

internal resistance of each battery = 2 ohm

Total emf of the circuit, E = E1 + E2 = 2 = 2 = 4 V

Now total internal resistance is

[tex]r = \frac{2\times 2}{2 + 2}= 1 ohm[/tex]

Total resistance, R = 4 = 1 = 5 ohm

Let the current is I.

E = I R

4 = I x 5

I = 0.8 A

Room heaters are placed on the floor of a room so that the air heated by it rises up and sets up the convection current in the room quickly and uniformly.

Explanation:

A the magnetic fields between the north poles repel each other

Explanation:

the correct answer is A

hpoe it help u

Answers:

The values are approximate.

==========================================================

Explanation:

When near the surface of the earth, the acceleration of gravity is roughly 9.81 m/s^2. This means that after each second passes, the velocity increases by roughly 9.81 m/s.

After 2.5 seconds, the velocity increases by 2.5*9.81 = 24.525 m/s = 24.5 m/s

If it was already going 25.0 m/s, then it bumps up to 25.0+24.5 = 49.5 m/s which is also approximate.

The acceleration of gravity stays the same when the object is close to the surface of the earth, so it stays at roughly 9.81 m/s^2

Side note: I'm ignoring air resistance (aka air friction or drag) since that greatly complicates things, and we would need to know the shape and surface area of the object. The material type would also be relevant info as well.

Answer:

Explanation:

If the force of 2000 N is directed towards the right and the friction is directed towards the left, the 2000 N force is positive and the other is negative. To find the resultant force:

2000 - 500 = 1500 N to the right

Answer:

DU = 375 Joules

Explanation:

Given the following data;

Quantity of heat = 500 Joules

Work done = 125 Joules

To find the change in internal energy;

Mathematically, the change in internal energy of a system is given by the formula;

DU = Q - W

Where;

Substituting into the formula, we have;

DU = 500 - 125

DU = 375 Joules

Explanation:

The Answer is B.I think so may be it's wrong so kindly get any confirmation from your teacher about this

Answer: Symbol is I and unit A

Explanation: A represents Amperes

HOPE THIS HELPS!!!!!!!!

Answer:

1028 slits/mm

Explanation:

We are given that

Wavelength of light, [tex]\lambda=530nm=530\times 10^{-9} m[/tex]

1nm=[tex]10^{-9} m[/tex]

[tex]\theta=33^{\circ}[/tex]

n=1

We have to find the number of slits per mm are marked on the grating.

We know that

[tex]dsin\theta=n\lambda[/tex]

Using the formula

[tex]dsin33^{\circ}=1\times 530\times 10^{-9}[/tex]

[tex]d=\frac{530\times 10^{-9}}{sin33^{\circ}}[/tex]

[tex]d=9.731\times 10^{-7} m[/tex]

1m=[tex]10^{3}mm[/tex]

[tex]d=9.731\times 10^{-7}\times 10^3[/tex]mm

[tex]d=0.0009731mm[/tex]

Number of slits=[tex]\frac{1}{d}[/tex]

Number of slits=[tex]\frac{1}{0.0009731}[/tex]/mm

Number of slits=1028/mm

Hence, 1028 slits/mm are marked on the grating.

Answer:

1027.6 lines per mm.

Explanation:

wavelength = 530 nm

order, m= 1

Angle = 33 degree

Let the slits per mm is 1/d.

So,

[tex]m \lambda = d sin A\\\\1\times 530\times 10^{-6} = d sin 33\\\\\frac{1}{d} = 1027.6 lines per mm[/tex]

Answer:

B

Explanation:

Eff = output work/input work ×100

Hence, Eff = 10000/12000 × 100

Eff = 83.3%

Answer:

Final volume, V2 = 3 Litres

Explanation:

Given the following data;

Initial volume, V1 = 1 litre

Initial temperature, T1 = 20°C

Final temperature, T2 = 60°C

To find the final volume, we would use Charles' law;

Charles states that when the pressure of an ideal gas is kept constant, the volume of the gas is directly proportional to the absolute temperature of the gas.

Mathematically, Charles is given by;

V1/T1 = V2/T2

Making V2 as the subject formula, we have;

V1T2 = V2T1

V2 = (V1T2)/T1

Substituting into the formula, we have;

V2 = (1 * 60)/20

V2 = 60/20

Final volume, V2 = 3 Litres

Answer:

A.

A battery in a pair of headphones

Explanation:

Potenial energy - the energy possessed by a body by virtue of its position relative to others, stresses within itself, electric charge, and other factors.