Need help ASAP plz and thank you!!

Answer:

The block hits the ground at 27.9 m/s

Explanation:

Gravitational Potential Energy (GPE)

It's the energy stored in an object because of its height in a gravitational field.

It can be calculated with the equation:

U=m.g.h

Where m is the mass of the object, h is the height with respect to a fixed reference, and g is the acceleration of gravity or [tex]9.8 m/s^2[/tex].

When the block is at the edge of the cliff it has potential energy that can be transformed into any other type of energy as it starts falling to the ground.

The GPE of the block of mass m=42 Kg at h=40 m is:

U = 42*9.8*40

U = 16,464 J

The block loses 81 J due to air resistance, thus the energy stored when it hits the ground is 16,464 J - 81 J = 16,383 J.

This energy is stored as kinetic energy, whose formula is:

[tex]\displaystyle K=\frac{1}{2}mv^2[/tex]

Solving for v:

[tex]\displaystyle v=\sqrt{\frac{2K}{m}}[/tex]

[tex]\displaystyle v=\sqrt{\frac{2*16,383 }{42}}[/tex]

[tex]v=\sqrt{780.143}[/tex]

v = 27.9 m/s

The block hits the ground at 27.9 m/s

Answer:

1.3

Explanation:

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Answer:

The force is [tex]F = 0.1441 \ N[/tex]

Explanation:

From the question we are told that

   The volume of blood ejected is  [tex]V_b = 65cm^3 = 65*10^{-6} \ m^3[/tex]

    The velocity of the ejected blood is  [tex]v = 98 cm/ s = 0.98 \ m/s[/tex]

    The mass density of blood is  [tex]\rho = 1060 \ kg/m^3[/tex]

    The heart rate is  [tex]R = 61 bpm(beats \ per \ miunite) = \frac{61}{60} = 1.0667\ bps[/tex]

Generally the average force exerted is mathematically represented as

     [tex]F = 2 * \rho * V_b * R * v[/tex]

=>   [tex]F = 2 * 1060 * (65*10^{-6}) *1.0667 * 0.98[/tex]

=>   [tex]F = 0.1441 \ N[/tex]    

because of gravitional pull

Answer:

Power_input = 85.71 [W]

Explanation:

To be able to solve this problem we must first find the work done. Work is defined as the product of force by distance.

 [tex]W =F*d[/tex]

where:

W = work [J] (units of Joules)

F = force [N] (units of Newton)

d = distance [m]

We need to bear in mind that the force can be calculated by multiplying the mass by the gravity acceleration.

Now replacing:

 [tex]W=m*g*d[/tex]

[tex]W=80*10*3\\W=2400[J][/tex]

Power is defined as the work done over a certain time. In this way by means of the following formula, we can calculate the required power.

 [tex]P=W/t[/tex]

where:

P = power [W] (units of watts)

W = work [J]

t = time = 40 [s]

[tex]P=W/t\\P=2400/40\\P=60 [W][/tex]

The calculated power is the required power. Now as we have the efficiency of the machine, we can calculate the power that is introduced, to be able to do that work.

 [tex]Effic=0.7\\Effic=P_{required}/P_{introduced}\\P_{introduced}= 60/0.7\\P_{introduced}=85.71[W][/tex]

Answer:

Electrical to Thermal

The maximum height reached by the squirrel : 0.479 m

Given

vo= 4 m/s

θ = 50 °

Required

The maximum height

Solution

Parabolic motion :

[tex]\tt h_{max}=\dfrac{v_o^2sin^2\theta}{2.g}[/tex]

Input the value

[tex]\tt h_{max}=\dfrac{4^2\times (sin~50)^2}{2\times 9.8}\\\\h_{max}=0.479~m[/tex]

or you can use

Find t from vt= vo sin θ - gt(negative sign=against gravity)⇒vt=0 at peak(the maximum height)

and input t to vertical component : y=voy.t-1/2gt²

Answer:

880J/kelvin

Explanation:

Q =MC ×change in t

c =C/m

C=Q/change in t

c= Q/ m× change in t

c = 26400 / 2.0 × 15

c = 880 J/kelvin

Answer;

2.6

Explanation;

Answer:

Explanation:

The density of a substance is the ratio of its mass to its volume. Its unit of measurement is kg[tex]m^{-3}[/tex].

i.e density, ρ = [tex]\frac{mass}{volume}[/tex]

1a. To determine the density of the acetic acid, Rachael needs to know the mass and volume of the acid.

i. Measure the mass of the given beaker using the mass balance.

ii. Transfer the acetic acid into the beaker, and measure the new mass using the mass balance.

iii. Subtract the mass of the beaker from the new mass to determine the mass of the acetic acid.

iv. Measure the volume of the acid on the scale of the beaker.

v. Divide the value of the mass by its volume to determine its density of the acetic acid.

b. Given that the density is 1.05 g/[tex]cm^{3}[/tex], and volume is 200 [tex]cm^{3}[/tex].

Then,

density = [tex]\frac{mass}{volume}[/tex]

1.05 = [tex]\frac{mass}{200}[/tex]

mass = 1.05 x 200

         = 210 g

mass = 210 g

2. Length of titanium = 0.40 m

   Area of titanium = 0.05 [tex]m^{2}[/tex]

mass = 90.0 kg

density = [tex]\frac{mass}{volume}[/tex]

But,

volume = area x length

            = 0.05 x 0.4

           = 0.02 [tex]m^{3}[/tex]

density of titanium = [tex]\frac{90}{0.02}[/tex]

                = 4500 kg[tex]m^{-3}[/tex]

Answer:

it implies our universe is expanding

Answer:

The force will be "[tex]9.8\times 10^{-3} \ N[/tex]".

Explanation:

The given values are:

Mass,

m = 1 gram

Angle,

Ф = 20°

As we know,

⇒ [tex]F=mg[/tex]

On substituting the given values in the above expression, we get

⇒     [tex]=(1.0\times 10^{-3})(9.8)[/tex]

⇒     [tex]=9.8\times 10^{-3} \ N[/tex]

Answer:

chemical potential of a species is energy that can be absorbed or released due to a change of the particle number of the given species, e.g. in a chemical reaction or phase transition.

Explanation:

Answer:

The value is  [tex]\Delta s = 8.537 *10^{25 } \ J/K[/tex]

Explanation:

From the we are told that

   The radius of the sphere is [tex]r = 6.32 *10^{8} \ m[/tex]

   The temperature is [tex]T_x = 5350 \ K[/tex]

    The average temperature of the rest of the universe is  [tex]T_r = 2.73 \ K[/tex]

Generally the change in entropy of the entire universe per second is mathematically represented as

         [tex]\Delta s = s_r - s_x[/tex]

Here [tex]s_r[/tex] is the entropy of the rest of the universe which is mathematically represented as

          [tex]s_r = \frac{Q}{T_r}[/tex]

Here Q is the quantity of heat radiated by the star which is mathematically represented as

           [tex]Q = 4 \pi * r^2 * \sigma * T^4_x[/tex]

Here [tex]\sigma[/tex] is the Stefan-Boltzmann constant with value  

           [tex]\sigma = 5.67 * 10^{-8 }W\cdot m^{-2} \cdot K^{-4}.[/tex]

=>         [tex]Q = 4 \pi * (6.32*10^{8})^2 * 5.67 * 10^{-8 } * 5350 ^4[/tex]

=>         [tex]Q = 2.332 *10^{26} \ J[/tex]

So

      [tex]s_r = \frac{2.332 *10^{26}}{2.73}[/tex]

=>   [tex]s_r = 8.5415 *10^{25}\ J/K[/tex]

Here [tex]s_x[/tex] is the entropy of the rest of the universe which is mathematically represented as

      [tex]s_x = \frac{Q}{T_x}[/tex]

=>   [tex]s_x = \frac{2.332 *10^{26} }{5350}[/tex]

=>   [tex]s_x = 4.359 *10^{22} \ J/K[/tex]

So

      [tex]\Delta s = 8.5415 *10^{25} - 4.359 *10^{22}[/tex]

=>   [tex]\Delta s = 8.537 *10^{25 } \ J/K[/tex]

This question involves the concepts of entropy and the thermal radiation

The entropy of the entire universe is increased by "8.41 x 10²⁵ J/k

".

The increase in entropy is given as follows:

[tex]\Delta s = s-s_T[/tex]

where,

Δs = increase in entropy = ?

σ = Stefan-Boltzman's constant = 5.67 x 10⁻⁸ W/m².k⁴

A = surface area = 4πr² = 4π(6.32 x 10⁸ m)² = 5.01 x 10¹⁸ m²

Tr = Absolute temperature of the star = 5350 K

T = absolute temperature of the rest of the universe = 2.73 k

Q = thermal radiation energy

Q = [tex]\sigma A T_r^4=(5.67\ x\ ^{-8}\ W/m^2.k^4)(5.01\ x\ ^{18}\ m^2)(5350\ k)^4=2.3\ x\ 10^{26}\ J[/tex]

s = entropy of the universe = [tex]\frac{Q}{T}=\frac{2.3\ x\ 10^{26}\ J}{2.73 k}=8.42\ x\ 10^{25}\ J/k[/tex]

[tex]s_T[/tex] = entropy of the star = [tex]\frac{Q}{T_r}=\frac{2.3\ x\ 10^{26}\ J}{5350\ k}=4.3\ x\ 10^{22}\ J/k[/tex]

Therefore,

Δs = 8.42 x 10²⁵ J/k - 4.3 x 10²² J/k

Δs = 8.41 x 10²⁵ J/k

Learn more about entropy here:

https://brainly.com/question/13146879?referrer=searchResults

Answer:

F=4500N

Explanation:

F=m×g

F=1500kg×3m/s²

F=4500N

Answer:

F=4500N

Explanation:

F=m×g

F=1500kg×3m/s²

F=4500N

Answer:

85.4 N

Explanation:

Weight of the ball, W = 60 N

W = mg, m is mass

m = W/g

m = 60/9.8 = 6.12 kg

Length of a rope, r = 6 m

Speed, v = 5 m/s

We need to find the tension in the rope at this point. Tension is equal to the centripetal force It is given by :

[tex]F=\dfrac{mv^2}{r}+mg\\\\F=\dfrac{6.12\times (5)^2}{6}+60\\\\=85.5\ N[/tex]

So, the correct option is (b) " 85.4 N".

Answer:

0.78 m

Explanation:

I just did a hw question for this its just 344  divided by 440

Answer:

C

Explanation:

covalent. Hope that helps!

Answer:

The apparent fit of the eastern coastline of South America and western coastline of Africa

Similarities of plants and animal fossils in South America and some parts of African continent which were separated by a vast ocean

Similarities in the sequence of rock layers of opposite sides of the Atlantic Ocean

Answer:

it takes him 22.36 seconds to cover that distance

Explanation:

We can solve this problem using the kinematic equation for uniformly accelerated motion:

[tex]x_f-x_i=v_0*t\,+\,\frac{1}{2} a\,*\,t^2[/tex]

which replacing the values given for our case becomes:

[tex]375=0*t\,+\,\frac{1}{2} (1.5)\,t^2\\375=\frac{1}{2} (1.5)\,t^2[/tex]

and which solving for t gives:

[tex]375=\frac{1}{2} (1.5)\,t^2\\t^2=2*375/1.5\\t^2=500\\t=\sqrt{500} \\t \approx 22.36\,\,sec[/tex]

Answer:

B. Planet X, because its line has the greater slope.

Explanation:

In a speed graph, acceleration is slope. A greater slope means a greater acceleration. According to Newton's 2nd law (F=mg), a greater acceleration means a greater force.

Planet X exerts the greater force of gravity on the sphere, because its line has the greater slope. Hence option B is correct.

Gravitational force is force of attraction between two masses. Gravitational force(F) between two bodies is directly proportion to the product of masses(m₁,m₂) of two bodies and inversely proportional to square of distance(r) between them. mathematically it is written as,

F ∝ m₁.m₂

F ∝ 1/r²

F = G m₁,m₂÷r²

where G is gravitational constant, whose value is 6.6743 × 10⁻¹¹ m³ kg-1s⁻².

Force is expressed in Newton N in SI unit. its dimensions are [M¹L¹T⁻²].

This is analogous with coulomb's law which gives force between two charges.

if a planet has greater gravitational force(force of gravity), then body falls with greater speed as compare to other planet which is having less force of gravity. we can see in case of planet X there is greater speed as compare to plane Y in short time. Hence option B is correct.

To know more about Gravity :

https://brainly.com/question/31321801

#SPJ2.

Answer:

with the increase in mass of the object , the force of gravitation increases that eventually increases the potential energy if the object is still fixed in its relative position with surrounding objects.

Explanation:

hopes this will help you

Answer:

i think it's d

Explanation:

Answer:

D

Explanation:

i feel like this one is it

Answer:

Power_input = 85.71 [W]

Explanation:

To be able to solve this problem we must first find the work done. Work is defined as the product of force by distance.

[tex]W = F*d[/tex]

where:

W = work [J] (units of Joules)

F = force [N] (units of Newton)

d = distance [m]

We need to bear in mind that the force can be calculated by multiplying the mass by the gravity acceleration.

Now replacing:

[tex]W = (80*10)*3\\W = 2400 [J][/tex]

Power is defined as the work done over a certain time. In this way by means of the following formula, we can calculate the required power.

[tex]P=\frac{W}{t}[/tex]

where:

P = power [W] (units of watts)

W = work [J]

t = time = 40 [s]

[tex]P = 2400/40\\P = 60 [W][/tex]

The calculated power is the required power. Now as we have the efficiency of the machine, we can calculate the power that is introduced, to be able to do that work.

[tex]Effic=0.7\\Effic=P_{required}/P_{introduced}\\P_{introduced}=60/0.7\\P_{introduced}=85.71[W][/tex]

Answer:

Force

Explanation:

Only a force can cause a stationary object to move or a moving object to change its speed or direction.

Answer:

NOOOOOOO NOT THE PACER TEST!!

Explanation:

MEMORIES OF MIDDLE SCHOOL I'D LIKE TO FORGET

also. LOL "Remember to run in a straight line" BRUH WE KNOW XDXD

Answer:

pressure=force/area

p=60N/(2m×1m)

=35N/M