Suppose you spend 30.0 minutes on a stair-climbing machine, climbing at a rate of 85 steps per minute, with each step 8.00 inches high. If you weigh 150 lb and the machine reports that 690 kcal have been burned at the end of the workout, what efficiency is the machine using in obtaining this result?

Answer:

1.4*10^6 J

Explanation:

Given that

Length of the propeller, l = 2.18 m

Mass of the propeller, m = 97 kg

Speed of the propeller, w = 2600 rpm

The formula for finding rotational Kinetic energy, K is = ½Iw²

Where, I is the moment of Inertia, and is given as 1/12 * m * l²

I = 1/12 * 97 * 2.18²

I = 8.083 * 4.7524

I = 38.41 kgm²

w = 2600 rpm, converting to rad/s, we have

w = 2600 * 2π rad/s

w = 272.31 rad/s

Now, Kinetic Energy, K is

K = ½Iw²

K = ½ * 38.41 * 272.31²

K = 19.205 * 74152.7361

K = 1424103.3 J

K = 1.4 MJ or 1.4*10^6 J

Thus, the rotational Kinetic Energy is 1.4*10^6 J

Answer:

1. c. Same in both

2. a. Case 1

Explanation:

1. The balls are identical in all sense, which means that if they are dropped from the same height, they should posses the same kinetic energy just before they collide with either the concrete floor or the stretchy rubber. Also, since they reach the same height when they bounced of the concrete floor or the piece of stretchy rubber, it means that they posses the same amount of kinetic energy at this point. Since their kinetic energy at these two points are the same, and they have the same masses, then this means that their momenta at these two instances will also be equal. Since all these is true, then the change in the momentum of the balls between the instance just before hitting the concrete floor or the stretchy rubber material and the instant the ball just leave the floor or the stretchy material is the same for both.

2. The ball that falls on the concrete will experience the greatest force, since the time of impact is small, when compared to the time spent by the other ball in contact with the stretchy rubber material; which will stretch, thereby extending the time spent in contact between them.

0.17T

When a charged particle moves into a magnetic field perpendicularly, it experiences a magnetic force [tex]F_{M}[/tex] which is perpendicular to the magnetic field and direction of the velocity. This motion is circular and hence there is a balance between the centripetal force [tex]F_{C}[/tex] and the magnetic force. i.e

[tex]F_{C}[/tex] = [tex]F_{M}[/tex]     --------------(i)

But;

[tex]F_{C}[/tex] = [tex]\frac{mv^2}{r}[/tex]   [m = mass of the particle, r = radius of the path, v = velocity of the charge]

[tex]F_{M}[/tex] = qvB [q = charge on the particle, B = magnetic field strength, v = velocity of the charge ]

Substitute these into equation (i) as follows;

[tex]\frac{mv^2}{r}[/tex] = qvB

Make B subject of the formula;

B = [tex]\frac{mV}{qr}[/tex]            ---------------(ii)

Known constants

m = 1.67 x 10⁻²⁷kg

q = 1.6 x 10⁻¹⁹C

From the question;

v = 1.4 x 10⁷m/s

r = 0.85m

Substitute these values into equation(ii) as follows;

B = [tex]\frac{1.67 * 10 ^{-27} * 1.4 * 10^{7}}{1.6 * 10^{-19} * 0.85}[/tex]

B = 0.17T

Therefore, the magnetic field strength is 0.17T

Answer:

on the left of the periodic table

Answer:

in the middle towards the left

Explanation:

just finished the quiz

Answer:

v₂₁ = 1.45 m/s

Second runner is the winner.

Δs = 35.1 m

Explanation:

For the relative velocity, we use the formula:

v₂₁ = v₂ - v₁

where,

v₂₁ = relative velocity of second runner with respect to first runner = ?

v₁ = velocity of first runner = 3.4 m/s

v₂ = velocity of second runner = 4.85 m/s

Therefore,

v₂₁ = 4.85 m/s - 3.4 m/s

v₂₁ = 1.45 m/s

Now, for finding the winner, we calculate the time taken by both the runners to reach finish line, by using following equation:

s = vt

t = s/v

for first runner:

t₁ = (215 m)/(3.4 m/s)

t₁ = 63.23 s

for 2nd runner:

t₂ = (215 m + 41.6 m)/(4.85 m/s)

t₂ = 52.9 s

Since, t₂<t₁.

Therefore, second runner is the winner.

Now, for the difference between runners at the time of winning, we first calculate the distance covered by first runner at that time. Using second equation of motion:

s = (3.4 m/s)(52.9 s)

s = 179.9 m

So, the distance by which the second runner finishes ahead of the first runner is given as follows:

Δs = 215 m - 179.9 m

Δs = 35.1 m

Answer:

Because as the waves propagates, the particles of the medium (molecules of water) vibrates perpendicularly (upward and downward) about their mean position and not in the direction of the waves.

Explanation:

A wave is a phenomena which causes a disturbance in a medium without any permanent deformation to the medium. Examples are; transverse wave and longitudinal wave. Waves transfer energy from one point in the medium to another.

The waves generated by water are transverse waves. Which are waves in which the vibrations of the particles of the medium is perpendicular to the direction of propagation of the waves.

Thus as the waves propagates, the molecules of water vibrates up and down and not along the direction of propagation of the waves. So that the floating objects do not get pushed in the direction of the waves every time.

Answer:

Gain heat and evaporate

Explanation:

As water molecules are exposed to sunlight, they begin to heat up. This means that the molecules begin to jiggle faster, and as such take up less space. Since they take up less space they are less dense, and therefore more bouyant. This means that they begin to rise into the air, and evaporate. Hope this helps!

Answer:

Explanation:

1.) Ratio of the speed of light in a vacuum to the speed of light in a medium is called refractive index. It is also known as index of refraction. It is a measure of light ray as they travel from one medium to another medium. We can determine the nature of a pair of media through their refractive indices.

2)   Rule for how light is refracted at the boundary between two materials is known as the Snell's law. Snell's law states that the ratio of the angle of incidence to the angle of refraction is a constant for a given pair of media. The angle incidence is greater than the angle of refraction if the light ray travels from less dense medium to a denser medium and lesser than the angle of refraction if the light ray travels from denser medium to a less dense medium.

3)  Process that occurs when the angle of incidence is greater than the critical angle is known as Total internal reflection. Total internal reflection only occurs when light rays travels from a denser medium to a less dense medium.

4.)  Path of a particle of light is known as Ray. A ray is a particle of light that emerge from the sun or a reflecting (luminous) body. They are in form of straight lines striking the surface of a body.

5.) Dispersion is defined as the separation of white light into into component color. This is accompanied with the use of a triangular glass prism. The white light is an example of electromagnetic spectrum. The component colors are known as ROYGBIV (Red, Orange, Yellow, Green, Blue, Indigo and violet.). This combination of colors are called rainbow.

The separation of light into different frequencies to produce a rainbow is therefore known as DISPERSION

Answer:

the size are components relative to the whole.

Explanation:

they are particularly good at showing percentage or proportional data

Answer:

a. the magnitude of the force experienced by the muon is 2.55 × 10⁻¹⁹N

b.  this force compare to the weight of the muon; the force is 1.38 × 10⁸ greater than muon

Explanation:

F= ma

v²=u² -2aS

(1.56 ✕ 10⁶)²=(2.40 ✕ 10⁶)²-2a(1220)

a=1.36×10⁹m/s²

recall

F=ma

F = 1.88 ✕ 10⁻²⁸ kg × 1.36×10⁹m/s²

F= 2.55 × 10⁻¹⁹N

the magnitude of the force experienced by the muon is 2.55 × 10⁻¹⁹N

b.  this force compare to the weight of the muon

F/mg= 2.55 × 10⁻¹⁹/ (1.88 ✕ 10⁻²⁸ × 9.8)

= 1.38 × 10⁸

Answer:

Option E, double the charge to 2, is the right answer.

Explanation:

Given the electric field at point = P

The point charge = Q

Distance =R

Magnitude = E

Due to a certain charge, the magnitude of the electric field at a point is defined as:

[tex]E = \frac{kQ}{r^2}[/tex]

Here, we can see that E is proportionate to Q and 1/r^2

Hence, double the charge to 2 and at the same time reduce the distance to /2 will half the E

Therefore, doubling the charge will doubling E

So the answer is (e) is correct.

Answer:

a) E = 2.7x10⁶ N/C

b) F = 54 N

Explanation:

a) The electric field can be calculated as follows:

[tex] E = \frac{Kq}{d^{2}} [/tex]

Where:

K: is the Coulomb's constant = 9x10⁹ N*m²/C²

q: is the charge

d: is the distance

Now, we need to find the electric field due to charge 1:

[tex] E_{1} = \frac{9 \cdot 10^{9} N*m^{2}/C^{2}*50 \cdot 10^{-6} C}{(0.5 m)^{2}} = 1.8 \cdot 10^{6} N/C [/tex]

The electric field due to charge 2 is:

[tex]E_{2} = \frac{9 \cdot 10^{9} N*m^{2}/C^{2}*(-25) \cdot 10^{-6} C}{(0.5 m)^{2}} = -9.0 \cdot 10^{5} N/C[/tex]

The electric field at a point midway between them is given by the sum of E₁ and E₂ (they are in the same direction, that is to say, to the right side):

[tex]E_{T} = E_{1} + E_{2} = 1.8 \cdot 10^{6} N/C + 9.0 \cdot 10^{5} N/C = 2.7 \cdot 10^{6} N/C to the right side[/tex]                                                                                                

Hence, the electric field at a point midway between them is 2.7x10⁶ N/C to the right side.  

b) The force on a charge q₃ situated there is given by:

[tex]E_{T} = \frac{F_{T}}{q_{3}} \rightarrow F_{T} = E_{T}*q_{3}[/tex]

[tex] F = 2.7 \cdot 10^{6} N/C*20 \cdot 10^{-6} C = 54 N [/tex]

Therefore, the force on a charge q₃ situated there is 54 N.  

I hope it helps you!

(a) The electric field at a point midway between [tex]q_1[/tex] and [tex]q_2[/tex] is obtained to be [tex]2.7\times 10^6 \,N/C[/tex].

(b) The electrostatic force on the third charge [tex]q_3[/tex] situated between [tex]q_1[/tex] and [tex]q_2[/tex] is obtained as 54 N.

The answer can be explained as follows.

Given that the two charges are;

(a) At the midpoint; [tex]r = 0.5\,m[/tex].

We know that the electric field due to charge [tex]q_1[/tex].

Where, [tex]k=9\times 10^9\,Nm^2/C[/tex]

The electric field due to charge [tex]q_2[/tex] is given by;

Therefore, the net electric field in the midpoint is given by;

The direction is towards the right side.

(b) Now, there is another charge [tex]q_3=20\times 10^{-6}[/tex] in the midpoint.

So the force on the charge is ;

Find out more about electrostatic force and fields here:

https://brainly.com/question/14621988

Answer:

48.64 m

Explanation:

From the question,

Range(R) = (U²Sin2Ф)/g.................. Equation 1

Where U = initial  velocity, Ф = Angle to the horizontal, g = acceleration due to gravity.

Given: U = 22 m/s, Ф = 40°, g = 9.8 m/s².

Substitute these values into equation 1

R = 22²Sin(40×2)/9.8

R = 484×0.9848/9.8

R = 48.64 m

Hence the range of the ball is 48.64 m

Answer:

a) m=1, y₁ = 0.08 m , θ₁ = 4.57º ,  b) m=2,  y₂ = 0.16 m , θ₂ = 9.09º ,  c)  m=3,   y₃ = 0.24 m ,   θ₃ = 13.5º

Explanation:

After reading your strange statement, I understand that this is an interference problem, I transcribe the data to have it more clearly. Number of slits 2, distance between slits 5000 nm, wavelength 400 nm, distance to the screen 1 m.

They ask us to calculate the angles for the first, second and third interference, they also ask us to write down the distance from the central maximum.

The expression for constructive interference for two slits is

             d sin θ = m λ

where d is the distance between the slits, λ is the wavelength used, m is an integer representing the order of interference

Let's use trigonometry to find the distance from the central maximum

         tan θ = y / L

in all interference experiments the angle is small,

         tan θ = sin θ / cos θ = sin θ

         sint θ = y / L

let's replace

        d y / L = m λ

        y = m λ L / d

let's calculate

distance to the first maximum m = 1

          y₁ = 1  400 10⁻⁹ 1/5000 10⁻⁹

          y₁ = 0.08 m

distance to second maximum m = 2

          y₂ = 2  400 10⁻⁹ 1/5000 10⁻⁹

          y₂ = 0.16 m

distance to the third maximum m = 3

          y₃ = 3  400 10⁻⁹ 1/5000 10⁻⁹

          y₃ = 0.24 m

with these values ​​we can search for each angle

           tan θ = y / L

           θ = tan⁻¹ y / L

for m = 1

            θ₁ = tan⁻¹ (0.08 / 1)

            θ₁ = 4.57º

for m = 2

            θ₂ = tan⁻¹ (0.16 / 1)

            θ₂ = 9.09º

for m = 3

            θ₃ = tan⁻¹ (0.24 / 1)

            θ₃ = 13.5º

Answer:

f = 357.29Hz

Explanation:

In order to calculate the fundamental frequency in the closed tube, you use the following formula:

[tex]f_n=\frac{nv}{4L}[/tex]       (1)

n: order of the mode = 1

v: speed of sound = 343m/s

L: length of the tube = 24cm = 0.24m

You replace the values of the parameters in the equation (1):

[tex]f_1=\frac{(1)(343m/s)}{4(0.24m)}=357.29Hz[/tex]

The fundamental frequency of in the tube is 357.29Hz

Answer:

Explanation:

The charge must be negative so that force in a downward electric field will be upward so that its weight is balanced .

Let the charge be - q .

force on charge

= q x E where E is electric field

= q x 680

weight = 1.6 x 10⁻³ x 9.8

so

q x 680 = 1.6 x 10⁻³ x 9.8

q = 1.6 x 10⁻³ x 9.8 / 680

= 23 x 10⁻⁶ C

- 23 μ C .

Answer:

Explanation:

a) The charge Q on the positive charge capacitor can be gotten using the formula Q = CV

C = capacitance of the capacitor (in Farads )

V = voltage (in volts) = 100V

C = ∈A/d

∈ = permittivity of free space = 8.85 × 10^-12 F/m

A = cross sectional area = 600 cm²

d= distance between the plates = 0.7cm

C = 8.85 × 10^-12 * 600/0.7

C = 7.59*10^-9Farads

Q = 7.59*10^-9 * 100

Q = 7.59*10^-7Coulombs

Q = 0.759*10^-6C

Q = 0.759µC

b) Energy stored in a capacitor is expressed as E = 1/2CV²

E = 1/2 * 7.59*10^-9 * 100²

E = 0.0000395Joules

E = 39.5*10^-6Joules

E = 39.5µJ

A) The charge Q on the positive plate of the capacitor is ; 0.759 µC

B) The energy stored in the capacitor increases by : 39.5 µJ

Given data :

Area of plates ( A ) = 600 cm²

Distance between plates ( d ) = 0.7 cm  

Voltage across plates = 100 v

∈ ( permittivity of free space ) =  8.85 * 10⁻¹²

A) Determine the Charge on the positive plate of the capacitor

Q = CV   --- ( 1 )

where ; C = ∈ * A / d   and  V = 100 v

∴ C = 8.85 * 10⁻¹² * 600 / 0.7  = 7.59 *10⁻⁹  F

Back to equation ( 1 )

Q = 7.59 *10⁻⁹  * 100

   = 0.759 µC

B) Calculate how much The energy stored in the capacitor increases

E = 1/2 * C * V²

   = 1/2 * 7.59 *10⁻⁹  * 100²

   = 39.5 µJ

Hence we can conclude that  The charge Q on the positive plate of the capacitor is ; 0.759 µC, The energy stored in the capacitor increases by : 39.5 µJ.

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Answer:

8.9 seconds

Explanation:

The height of the object at time t is:

y = h + vt − 4.9t²

where h is the initial height, and v is the initial velocity.

Given h = 30 and v = 40:

y = 30 + 40t − 4.9t²

When y = 0:

0 = 30 + 40t − 4.9t²

4.9t² − 40t − 30 = 0

Solving with quadratic formula:

t = [ -(-40) ± √((-40)² − 4(4.9)(-30)) ] / 2(4.9)

t = [ 40 ± √(1600 + 588) ] / 9.8

t = 8.9

It takes 8.9 seconds for the object to land.

Answer:

[tex]V = 331.6946\ m/s[/tex]

Explanation:

First let's find the time that takes the shell to hit the ground (height zero).

To find this time, we can use the equation:

[tex]S = So + Vo*t + at^2/2[/tex]

Where S is the final position, So is the inicial position, Vo is the inicial speed, a is the acceleration and t is the time. Then, for the vertical movement of the shell, we have that:

[tex]0 = 80 + 0*t - 9.81*t^2/2[/tex]

[tex]9.81*t^2/2 = 80[/tex]

[tex]t^2 = 160/9.81 = 16.31[/tex]

[tex]t =4.0386\ seconds[/tex]

Now, to find the horizontal speed, we use the equation:

[tex]S = So + V*t[/tex]

Then, for the horizontal movement, we have:

[tex]1330 = 0 + V_h * 4.0386[/tex]

[tex]V_h = 1330/4.0386 =329.32\ m/s[/tex]

Now we need to find the vertical speed, using:

[tex]V = Vo + a*t[/tex]

[tex]V_v = 0 - 9.81*4.0386[/tex]

[tex]V_v = -39.6187\ m/s[/tex]

Finally, to find the magnitude of the velocity, we have:

[tex]V = \sqrt{V_h^2 + V_v^2}[/tex]

[tex]V = \sqrt{329.32^2 + (-39.6187)^2}[/tex]

[tex]V = 331.6946\ m/s[/tex]

Answer:

The number of turns present in the loop are 625 turns.

Explanation:

Given;

current on the rectangular loop, I = 6A

Dimension of the rectangular loop, L x B = 0.04 m × 0.08 m

Magnetic moment of the loop, Pm = 12 Am²

Area of the rectangular loop, A =  L x B = 0.04 m × 0.08 m = 0.0032 m²

The magnetic moment of plane carrying coil/loop is given as;

Pm = NIA

Where;

N is the number of turns

A is the area of the loop

I is the current on the loop

[tex]N = \frac{P_m}{IA} \\\\N = \frac{12}{6*0.0032}\\\\N = 625 \ turns[/tex]

Therefore, the number of turns present in the loop are 625 turns.

Answer:

4L

Explanation:

Data provided in the question according to the question is as follows

Length = L

Gravity = G

For friend

Length = ?

Growth = 4G

Moreover,

[tex]T_1 = T_2[/tex]

Based on the above information ,

Now we have to apply the simple pendulum formula which is shown below:

[tex]T = 2\pi \frac{L}{G}[/tex]

Now equates these equations in both sides

[tex]2\pi \frac{L}{G} = 2\pi \frac{L}{4G}[/tex]

So after solving this, the length of the pendulum is 4L

Answer:

the length of a pendulum on your friend s planet should be 4 times than that on earth

Explanation:

We know that time period of simple pendulum is given by

[tex]T= 2\pi\sqrt{\frac{L}{g} }[/tex]

L= length of pendulum

g= acceleration due to gravity

therefore, Let T_1 and T_2 be the time period of the earth and other planet respectively.

[tex]\frac{T_1}{T_2} =\sqrt(\frac{L_1}{L_2}\times\frac{g_2}{g_1})[/tex]

ATQ

T_1=T_2=T,   g_2=4g_1

Putting the values in above equation and solving we get

[tex]\frac{L_1}{L_2} =\frac{1}{4}[/tex]

Answer:

The answer is A

Explanation:

Its A because he created a telescope to be able to observe stars.

Answer:

Majorly the electric field is reduced among other effect listed in the explanation

Explanation:

In capacitors the presence of di-electric materials

1. decreases the electric fields

2. increases the capacitance of the capacitors.

3. decreases the voltage hence limiting the flow of electric current.

 The di-electric material serves as an insulator between the metal plates of the capacitors

Answer:

(a)2.865 s

(b)2.865 s

Explanation:

We are given that

Acceleration,a=[tex]3.49 m/s^2[/tex]

a.Initial speed,u=29 m/s

Final speed,v=39 m/s

We know that

[tex]t=\frac{v-u}{a}[/tex]

Using the formula

[tex]t=\frac{39-29}{3.49}=2.865 s[/tex]

b.Initial speed,u=59 m/s

Final speed,v=69 m/s

Again using the formula

[tex]t=\frac{69-59}{3.49}=2.865 s[/tex]

Answer:

The effective (rms) current when the circuit is in resonance is 6 A

Explanation:

Given;

resistance of the resistor, R = 20 ohms

capacitance of the capacitor, C = 0.75 microfarads

inductance of the inductor, L =  0.12 H

effective rms voltage, [tex]V_{rms}[/tex] = 120

At resonance, the impedance Z = R, Since the capacitive reactance (Xc) is equal to inductive reactance (XL).

The effective (rms) current, = [tex]V_{rms}[/tex] / R

                                              = 120 / 20

                                              = 6 A

Therefore, the effective (rms) current when the circuit is in resonance is 6 A

Explanation:

Einsteins theory of relativity explains how space and time are linked for objects that are moving at a consistent speed in a straight line.

Answer:

Mass of water displaced = 1.6 kg

Explanation:

given data

Mass of brick m = 4kg

Density of water d₁ = 1000kg/m³

Density of brick d₂ = 2.5 g/cm³ = 2500 kg/m³

solution

we get here first volume of brick  that is

volume of brick =  m ÷ d₂     ..................1

put here value and we get

volume of brick = 4 ÷ 2500

volume of brick = 0.0016 L

and

we will use here Archimedes' Principle formula of the buoyant force

as buoyant force = the weight of the liquid displaced by an object

so now we get here Buoyant Force that is express as

Buoyant Force = v × d₁ × g     ........................2

put here value

Buoyant Force = 0.0016 × 1000 × 9.8

Buoyant Force = 15.68 Newtons

so

Buoyant Force = Weight of the water displaced     .................3

Buoyant Force = Mass of water displaced × g

and

weight = mass × acceleration due to gravity     .......................4

so put here value and we will get

15.68 = mass of brick × 9.8

Mass of water displaced = 1.6 kg

Answer:

2.95m

Explanation:

Using h= 2.5+ v²/2g

Where v= 3m/s

g= 9.8m/s²

h= 2.95m

Answer:

D. All of the above

Explanation:

The last stage in the Marcia's identity formation theory is Identity achievement. In this last stage, teens have made a thorough search or exploration about their identity and have made a commitment to that identity. This identity represents their values, beliefs, and desired goals. At this point, they know want they want in life, and can now make informed decisions based on their belief and ideology.

James Marcia is a psychologist known mainly for his research and theories in human identity. Identity according to him is the sum total of a person's beliefs, values, and ideologies that shape what a person actually becomes and is known for. Occupation and Ideologies primarily determine identity. The four stages of Identity status include, Identity diffusion, foreclosure,  moratorium, and achievement.

Answer:

The correct answer is option 3 .

Please check the answer once :)