what fraction of the energy density of the universe is dark matter? group of answer choices 71% 5% 1% 24% 99%

7.095 × 10⁵ KHz is the frequency of an electromagnetic wave that has the same wavelength as a 3.5 KHz sound wave in water.

The pace at which current changes direction each second is known as frequency. One hertz (Hz), which is a unit of measurement used internationally, equals one cycle per second. One hertz (Hz) is one cycle every second. A full alternating current or voltage wave is referred to as a cycle.

The number of waves that pass a specific place in a predetermined period of time is known as the wave frequency. A wave passes a fixed point in one hertz (Hz), the SI unit for wave frequency, in one second. A wave with a higher frequency has more energy than a wave with a lower frequency of the same amplitude.

Given that,

frequency = 3.5 KHz

As we know,

V = fλ

As, the electromagnetic wave that has the same wavelength, thus

V/f = constant

Therefore,

V₁/V₂ = f₁/f₂

now, f₁ =  (V₁/V₂)× f₂

or, f₁ = [(3 × 10⁸) / 1480] × (3.5 × 10³)

or, f₁ = 7.095 × 10⁸ Hz

or, f₁ = 7.095 × 10⁵ KHz.

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Work is the transmission of energy over a specific distance in one direction with the aid of a force. The force that operates at a specific distance is another name for energy.

Both of them fit the definition of a scalar unit. There must be a force and movement from one location to another for labor to take place.

Energy can be transmitted to or from an object when two things interact because of the forces that each one of the items applies to the other. For instance, the gravitational field energy of a system including the Earth and an object grows as energy is transmitted to the system when the object is raised. Power is the amount of work completed in a given amount of time. In order to learn new information and achieve higher exam scores, studying requires a lot of energy.

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The rotating equivalent of linear momentum in physics is called angular momentum, also known as moment of momentum or rotational momentum.

Conservation of Angular Momentum m v (L/2) = I w => w^2 = m^2 v^2 L^2/(4 I^2)---------eq1

Conservation of Energy (1/2) I w^2 = (m + M)g h----------------eq2 where h = height of the center of mass

Relate h to h': h' = height from the bottom a= angle between rod and the normal

(L/2 -(L/2) cos(a)) = h (L - L cos(a))=h' => h=h'/2--------------------------eq3

Compute I=moment of inertia I=m(L/2)^2 + (1/12) M L^2 + M(L/2)^2 I= [(L^2)/4](m + 4M/3)------------------eq4

Plug eq1 and eq3 into eq2 (1/2) I m^2 v^2 L^2/(4 I^2) = (m + M)g h'/2 Solve for h' h'=m^2 v^2 /((m + M)g)

Then use eq4 to get the final result h'=m^2 v^2 /((m + 4M/3)(m + M)g)

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The kinetic energy of a solid sphere is (1/2)mv² + [(2/5)mr²] × ω² × r  for having mass m and radius r rolls without slipping.

We know that if property of sphere is defined, it means that linear and rotational kinetic energy is possible.

For rotational energy, we need to know about moment of inertia and angular acceleration.

For solid sphere moment of inertia is given by the expression=(2/5)mr² where m is the mass and r is the radius of the sphere

Now, we know that for angular acceleration we need angular velocity which can be calculated by the linear velocity which can be calculated by the formula

v=ω×r where v is the linear velocity ,ω is angular velocity and r is the radius of the object.

So,ω=v/r

Now we know that angular acceleration(α)=ω² × r

Therefore, rotational energy is =I × α = [(2/5)mr²] × ω² × r

Now, we know that kinetic energy is given by =(1/2)mv² where m is the mass and v is the velocity of a solid sphere.

So, kinetic energy of sphere is =linear kinetic energy + rotational kinetic energy

=>kinetic energy = (1/2)mv² + [(2/5)mr²] × ω² × r

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The reading on the bathroom scale is W = 230 lbs.

Solution:

Since acceleration is zero, so weight remains the same on scale

W = 230 lbs

Acceleration is the rate of change of velocity over time, both in terms of velocity and direction. A point or object moving in a straight line accelerates as it accelerates or decelerates. Circumferential motion is accelerated because it always changes direction even at constant velocity.

Acceleration is the change in velocity over time. Whenever a change in velocity or acceleration in the direction of movement occurs. At constant velocity, acceleration is zero. Deceleration is called negative acceleration or deceleration.

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The radiation of the cosmic microwave background today is blank and has most of its photons at longer wavelengths.

Gamma rays have extremely small wavelengths that are only a small portion of the size of atoms, whereas other wavelengths can extend as far as the universe because the relationship between wave frequency and wavelength is inverse. Although it isn't always stated explicitly, electromagnetic radiation's wavelengths are typically expressed in terms of the vacuum wavelength, regardless of the medium they are traveling through. Electromagnetic radiation's behavior is influenced by its wavelength. wavelength x frequency equals the speed of light. Energy equals Planck's constant times frequency. Wave number in cm equals 1/wavelength. A rough estimate of the wavelength size is shown along with the wavelengths of various regions of the electromagnetic spectrum.

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A motorcycle has a mass of 250 kg. it goes around a 13.7 m radius turn at 96.5 km/h. 9720 N is the centripetal force on the motorcycle.

To find the centripetal force on the motorcycle, we can use the formula for centripetal force:

F = m * a

where F is the centripetal force, m is the mass of the object, and a is the centripetal acceleration. To find the centripetal acceleration, we can use the formula for centripetal acceleration:

a = v^2 / r

where a is the centripetal acceleration, v is the velocity, and r is the radius of the curve. In this case, we know that the mass of the motorcycle is 250 kg, the velocity is 96.5 km/h, and the radius of the curve is 13.7 m. To find the centripetal acceleration, we need to convert the velocity from km/h to m/s. Since 1 km/h is equal to 1000 m/3600 s = 0.2778 m/s, the velocity in m/s is 96.5 km/h * 0.2778 m/s/km/h = 26.7 m/s.

For centripetal force and centripetal acceleration, we get:

F = m * a

= 250 kg * (v^2 / r)

= 250 kg * (26.7 m/s)^2 / 13.7 m

= 9720 N

Therefore, the centripetal force on the motorcycle is 9720 N.

Gravity is the centripetal force that drives astronomical orbits according to Newtonian mechanics. The tension of the rope provides the centripetal force on an object that is swinging around on the end of a rope in a horizontal plane. The rope illustration is a pull-related example. In some situations, such as when a wall's natural reaction serves as the centripetal force for a wall of death or a Rotor rider, the centripetal force can also be provided as a "push" force.

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The kinetic energy is 2.88 × 10-17 J and the velocity of the proton will be 180 m/s

The kinetic energy of the proton is given by

 KE = qV = (1.60217662 × 10-19 C) (360 N/C) (0.50 m)

= 2.88 × 10-17 J,  The velocity of the proton is given by:

 V = (360 N/C) (0.50 m) =0.360 x 0.50 = 0.180 m/s .

This means that after the proton has traveled 50 cm, it will have a kinetic energy of 2.88 × 10-17 J and a velocity of 180 m/s. This result is because the electric field is uniform and constant, and the proton is accelerated by the same amount throughout its journey. This means that the velocity and kinetic energy of the proton will increase linearly with the distance traveled. The electric field provides the proton with a constant acceleration, and as the proton travels further, it gains more kinetic energy and a higher velocity.

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There are 17.1 revolutions per minute will the riders be subjected to a centripetal acceleration 1.50 times that due to gravity

Acceleration is the rate at which velocity changes over time, both in terms of speed and direction. A point or object travelling in a straight path is accelerated if it accelerates or decelerates. Even if the speed is constant, motion on a circle is accelerated because the direction is always changing.

The centripetal acceleration can be written as: a =

r \sω \s²

Where is the angular velocity. Equating this to the question: r²= 2.25 g

7.00 2 = 2.25 9.81

When we solve for, we get: = 1.78

Angular velocity is defined as the rate of change of angle = 2 T.

Where T is the time span (time for one revolution)

As a result, we can solve for T.

= 3.5

As a result, it completes one rotation every 3.5 seconds. It will finish in one minute:

60 /3.5

= 17.1 rotations.

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Three times as massive as the Sun is the white dwarf star in the heart of the Helix planetary nebula. False The Chandrasekhar mass, or 1.4 solar masses, is the white dwarf's maximum mass.

White dwarf stars typically last between 100,000 and 10 billion years and have masses between 0.1 and 1.4 that of the Sun. To balance their mass, white dwarf stars no longer produce energy. White dwarf stars, like Sirius B, Procyon B, or Van Maanen, are limited in mass theoretically to 1.4 solar masses.

A star core remnant known as a white dwarf is primarily made up of electron-degenerate materials. A white dwarf is extremely dense; it has a mass similar to that of the sun.

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The distance of galaxy is given as 5Mpc. and the Hubble's constant is 70(km/s)/Mpc.

To find the recessional velocity of the galaxy

Hubble found that the tendency of recessional velocity is to increase with the distance of galaxy, therefore recessional velocity is directly proportional to the distance of the galaxy

The relation between recessional velocity and the distance of the galaxy can be expressed using Hubble's law.

substituting the values we get

V=70 (km/s)/ mpc [tex]\times[/tex]5Mpc

V = 350km,

Therefore the recessional velocity will be 350 km/s.

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The field of science that deals with the practical application of a liquid in motion is called fluid mechanics.

The fluid mechanics is the branch of science that deals with the practical application of a liquid when it is in motion or in rest.

Pascal's law, equation of continuity and Bernoulli's equation all comes under the study of fluid mechanics.

Fluid mechanics is the field of science because of which we are able to make the break of the vehicles hydraulic lift hydraulic press and many more things. We are able to make the Barometer, thermometer and many other things because of the practical applications of fluid mechanics.

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a) In this part of the problem, we are calculating the integral of the velocity function from t = 60 seconds to t = 120 seconds.

b) Next, we have a similar integral. The velocity function is now, however, contained by absolute value bars. Our velocity function will only equal to positive values as a result.

c) The acceleration function is the subject of our last integral.

a) When we integrate a velocity function, we return to the position function. As a result, this integral is determining the particle's displacement by determining the difference in location between these two points.

b) The result of this integration will treat all traveled distances as positive values as well, even if the particle moves backwards. This integral will determine the overall distance travelled during this period, rather than the displacement between 120 and 60 seconds.

c) When we integrate an acceleration function, we return to the velocity function. Thus, this integral will calculate the total change in the velocity between 60 seconds and 120 seconds.

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The speaker's power output is 785.398 W assuming uniform spherical spreading of the sound and neglecting absorption in the air.

Given the Sound Intensity = I and

the Loudspeaker Distance = r = 2.5m

Sound level produced(β) : 130 dB

The formula for calculating sound intensity is:

β = 10logI/I0

130 = 10logI/10-12

13 = logI/10-12

10^13x10^-12 = I

I = 10 W/m^

A = area, hence power (P) = IA = 4πr^2

P = 10X 4X 3.14X (2.5)^

P = 785.398W

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At a rock concert, a dB meter registered 130 dB when placed 2.5 m in front of a loudspeaker on stage. (a) What was the power output of the speaker, assuming uniform spherical spreading of the sound and neglecting absorption in the air?

The solid that is located above the rectangle and beneath the plane 4x+6y-2z+15 has a volume of 51 liter.

The amount of space that a solid occupies is measured by its volume. The amount of unit cubes required to completely fill the solid serves as the measurement. There are 30 unit cubes total in the solid, hence the volume is 2 units. 3 units 30 cubic units from 5 units.

Formula for Solids Volume. Let's have a look at the volumes of all the three-dimensional solid shapes before we answer the problems based on the combination of solids. The formula for volume and surface area for a cuboid with dimensions of length (l), breadth (b), and height (h) is provided by: Volume = lbh.

[tex]4x+6y-2z+15=0\\2z=4x+6y+15\\z=2x+3y+ \frac{15}{2}\\[/tex]

The volume for the given solid is,

[tex]\\V= \int_{-1}^{1 } \int_{-1}^{2} \left ( 2x+3y+ \frac{15}{2} \right ) dy/dx\\V= \int_{-1}^{1 } \left [ \frac{2x^2}{2}+3xy+\frac{15x}{2} \right ]_{-1}^{2}\\V= \int_{-1}^{1 } \left [ x^2+3xy+\frac{15x}{2} \right ]_{-1}^{2}\\V= \int_{-1}^{1 } \left [ 2^2+3*2y+\frac{15*2}{2}-\left ( (-1)^2+3*-1y+\frac{15*-1}{2} \right ) \right ]\\[/tex]

[tex]V= \int_{-1}^{1 } \left [ 4+6y+\15-\left ( 1-3y-\frac{15}{2} \right ) \right ]\\V= \int_{-1}^{1 } \left [ 4+6y+\15- 1+3y+\frac{15}{2} \right ]\\V= \int_{-1}^{1 } \left [ 3+9y+\frac{45}{2} \right ]\\V= \int_{-1}^{1 } \left [ 9y+\frac{51}{2} \right ]\\V= \left [ \frac{9y^2}{2}+\frac{51 y}{2} \right ]_{-1}^{1 }\\V= \left [ \frac{9*1^2}{2}+\frac{51 *1}{2}-\left ( \frac{9*(-1)^2}{2}+\frac{51 *-1}{2} \right ) \right ]\\[/tex]

[tex]V= \left [ \frac{9}{2}+\frac{51 }{2}-\left ( \frac{9}{2}-\frac{51}{2} \right ) \right ]\\V= \left [ \frac{9}{2}+\frac{51 }{2}- \frac{9}{2}+\frac{51}{2} \right ]\\V= \left [ \frac{51 }{2}+\frac{51}{2} \right ]\\V= 51[/tex]

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Answer:

Below

Explanation:

The area under the graph will represent the displacement .

  Remember   displacement =   velocity * time

     so the total displacement will be Area 1  -  Area 2

Answer:

Production of wastes needing long-term storage

Explanation:

As you move the object closer and closer to the focal point, the image will become further and further away kind of image results from putting anything in front of the focal

A converging lens's focal point is just outside the image result for an item. explain the picture (mark all that apply).

In reality, it is possible to generalize that the image will always be situated behind the mirror whenever the item is situated between the focal point (F) and the mirror. In certain circumstances, the image will be larger than the thing and upright (not inverted).

Kind of image results from sandwiching an object between No image is created when the object is at the focal point. although the refracted beams do not converge or diverge. The light rays cannot create an image since they are moving parallel to one another after refractive error.

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The acceleration of the ball during the contact is 1652  m/s^2 in upward direction.

Acceleration is rate of change of velocity with time. Due to having both direction and magnitude, it is a vector quantity. Si unit of acceleration is meter/second² (m/s²).

The velocity of the ball before hitting the floor in downward direction:

u = √(2gs)

= √(2×9.8×4) m/s

= 8.85 m/s.

The velocity of the ball after hitting the floor in upward direction:

v  = √(2gs)

= √(2×9.8×3) m/s

= 7.67 m/s.

Hence, the acceleration of the ball during the contact in upward direction is: a = change in velocity/time duration

= (7.67 - (-8.85))/0.01 m/s^2

= 1652  m/s^2

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The  best response that shari’s friend could make was that She could disagree with Shari because the pendulum converts gravitational potential energy into kinetic energy, then back into gravitational potential energy.

The ball is momentarily immobile at the height of the swing. Due to its elevated position above the surface, it possesses the maximum potential energy. The system of the ball on the pendulum string has the same overall quantity of energy at every point in the swing.

The pendulum's energy is continuously transformed from gravitational potential to kinetic, and vice versa. The pendulum on the left swings more quickly than the pendulum on the right because shorter pendulums swing more quickly than larger ones do.

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In a case whereby cosmic microwave background is almost perfectly uniform in all directions, except for very small deviations in its temperature. what the scientists think these small deviations represent is d. regions of slightly density that made it possible for galaxies form.

The Cosmic Microwave Background  can be descibed as the cooled remnant of the first light  which could ever travel freely throughout the Universe it can be seen as the 'fossil' radiation, which an be considered as the furthest that any telescope can see.

It should be noted that the  density i can be of two types,  whereby one is absolute density, and the other is relative density hgowever the Relative density  can be described as the specific gravity,  and this is the ratio of the density of a material to the density of reference material.

Therefore, option D is correct.

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Due of Earth's far bigger orbit than Mars', as Earth passes it, Mars seems to be going backwards. Ptolemy postulated that planets orbited on epicyles that revolved around deferents to explain this.

Mars experiences retrograde motion when Earth, which moves more quickly than Mars, passes it. Due to this, Mars seems to move westward in retrograde motion, which is the real or apparent travel of a body in a direction that differs from that of the majority of solar system members' (direct) movements or the motion of other astronomical systems with a preferred direction of motion. All of the planets, with the exception of Venus and Uranus, rotate counterclockwise on their own axes as seen from a location in space north of the solar system (from a large distance above the North Pole of the Earth). Venus and Uranus, therefore, exhibit retrograde rotation. Fewer than half of the known satellites of the planets exhibit retrograde rotation.

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The change in the systems internal energy is 400KJ.

ΔE = Q - W

but, Qin > 0

       Win < 0

ΔE  = 850 - 450 = 400KJ

As with the static rest mass energy of its constituent matter, the internal energy cannot be readily measured, and knowledge of all of its components is rarely interesting. In contrast to its absolute value, the internal energy is only primarily concerned with changes in thermodynamics. Instead, it is typical to specify a reference state and gauge how a thermodynamic process differs from this state. Matter is transferred, energy is released as heat, or thermodynamic work is performed to change the internal energy. The system's attributes, including changes in temperature, entropy, volume, and molar composition, are used to measure these processes. The system is referred to as closed when matter transfer is inhibited by impermeable containment walls. Neither matter if the confining walls fail.

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Answer:

Assuming air resistance is neglected and the only force acting on the branch is the acceleration due to gravity, the answer is 716.709768 meters.

Explanation:

Since the initial velocity is 0, the displacement s, is simply written as :

s = (1/2)gt².

where g is the acceleration due to gravity.

The statement "when making your turn you should accelerate at the apex of the turn" is false.

It is generally not advisable to accelerate at the apex of a turn. In fact, it is generally recommended to slow down or maintain a constant speed while turning, in order to maintain control and avoid oversteering.

Accelerating at the apex of a turn can cause the vehicle to lose traction and potentially lose control. This is especially true if the surface is slippery or the vehicle is traveling at a high speed.

Instead of accelerating at the apex of a turn, it is generally recommended to gradually increase speed as the vehicle exits the turn, once it is back on a straight stretch of road. This allows the vehicle to maintain stability and control while turning, and helps to prevent accidents.

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The area of the region that lies inside both curves r² = 2sin(2θ), r = 1 is -0.1287 square units.

Since the curves are:

r² = 2sin(2θ) and

r = 1.

We find their point of intersection.

So, r² = r²

= 2sin(2θ) = 1²

= 2sin(2θ) = 1

= sin(2θ) = 1/2

= 2θ = sin⁻¹(1/2)

= 2θ = π/6

= θ = π/12

Thus, we integrate the area from θ = 0 to θ = π/12

Now the area A of the region between two curves between θ = α to θ = β is =

= A = ∫ (r²-r'²) dθ    [from 0 to π/12]

So, the area between the curves r² = 2sin(2θ),  r = 1 between θ = 0 to θ = π/12 is =

= A = ∫ (r²-r'²) dθ       [from 0 to π/12]

= A = (2sin2θ dθ - 1²) dθ       [from 0 to π/12]

= A = 0.1278

So, the area of the region that lies inside both curves r² = 2sin(2θ),  r = 1 is -0.1287 square units.

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A beam of light in the air encounters a transparent block with index of refraction n=1.53. Some of the light is reflected and some is refracted. There will be no such angle of incidence between [tex]$0^{\circ}$[/tex] and [tex]$90^{\circ}$[/tex] such that all of the light will be reflected.

In geometric optics, the angle of incidence is the angle between a ray incident on a surface and the normal, or line perpendicular to the surface at the point of incidence. Any type of wave, including microwave, X-ray, optical, and acoustic, may create a ray.

The refractive index of an optical medium is a dimensionless quantity that indicates how well that medium bends light in optics. The refractive index controls how much light is refracted or twisted when it enters a substance.

[tex]\begin{aligned}\mu & =\frac{1}{\sin c} \\c & =\sin ^{-1}\left(\frac{1}{\mu}\right) \\& =\sin ^{-1}\left(\frac{1}{1.53}\right) \\& =40.83\end{aligned}[/tex]

First condition it should be remembered that if the incident angle is from denser medium to rarer medium at or greater than [tex]$40.33^{\circ}$[/tex], all light will be reflected but in this Question, the condition is the opposite.

Hence, there should not be such an angle.

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The complete question should be:

A beam of light in the air encounters a transparent block with index of refraction n=1.53. Some of the light is reflected and some is refracted.

Is there an angle of incidence between [tex]$0^{\circ}$[/tex] and [tex]$90^{\circ}$[/tex] such that all of the light will be reflected?

(a) Yes, at an angle greater than [tex]50^{\circ}[/tex]

(b) Yes, at an angle less than [tex]50^{\circ}[/tex]

(c) No.

The daily equivalent of 6.27 106 joules is 1500 calories, which the average person consumes daily. This is roughly equivalent to the energy needed to drive a car for 15 minutes.

Even while sleeping, a creature still needs energy. This is because our bodies continue to go through a variety of energy-intensive biological processes when we sleep.

Even when we are asleep, our hearts continue to beat in order to circulate blood throughout the body. Additionally, the heart requires energy to beat. As a result, the heart requires a constant flow of energy to function.

Therefore, 1 watt = 1 joule/second, so  100 w there needs to be 100 joules.

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Answer:

[tex]8.4\; {\rm m\cdot s^{-1}}[/tex].

Explanation:

Let [tex]x[/tex] denote the displacement of the ball. It is given that [tex]x = 12\; {\rm ft}[/tex]. Apply unit conversion and ensure that the displacement [tex]x\![/tex] of the ball is measured in meters:

[tex]\begin{aligned}x &= (12\; {\rm ft})\, \frac{(0.30\; {\rm m})}{(1\; {\rm ft})} = 3.6\; {\rm m}\end{aligned}[/tex].

Let [tex]u[/tex] denote the initial velocity of the ball, and let [tex]v[/tex] denote the velocity of the ball right before it hits the ground. Note that since the question states the ball was "dropped", assume that the ball was initially at rest with initial velocity [tex]u = 0\; {\rm m\cdot s^{-1}}[/tex].

Under the assumptions, the acceleration [tex]a[/tex] of the ball will be constantly [tex]a = g = 9.8\; {\rm m\cdot s^{-2}[/tex].

Rearrange the SUVAT equation [tex]v^{2} - u^{2} = 2\, a\, x[/tex] to find the final velocity [tex]v[/tex] of the ball right before landing:

[tex]\begin{aligned}v &= \sqrt{u^{2} + 2\, a\, x} \\ &= \sqrt{(0\; {\rm m\cdot s^{-1}})^{2} + 2\, (9.8\; {\rm m\cdot s^{-1}})\, (3.6\; {\rm m})} \\ &= 8.4\; {\rm m\cdot s^{-1}}\end{aligned}[/tex].

Answer: B (8.4 m/s)

Explanation:

An object in free fall has a speed of 60 m/s. One second later its speed is 70m/s.

We're asked to find the speed of an object in free fall one second after it has a speed of 60m/s. An object in free fall means that the only force affecting its motion is gravity. To do this, we can use the equation

vy=v°y+ayt

where:

Plugging in known values, we have Vy=60m/s(9.81m/s²)(1s) =-70m/s rounded to 2 (or 1, technically) significant figures.

This the velocity of the object (which is why it includes a sign). The speed is simply the magnitude of this, which is a positive quantity.

speed = 70m/s

You also could have solved this problem neglecting the signs of the initial velocity and acceleration in the above equation:

speed = 60m/s +(9.81m/s²)(1s) = 70m/s

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