The knee extensors insert on the tibia at an angle of 30 degrees (from the longitudinal axis of the tibia), at a distance of 3 cm from the axis of rotation at the knee. How much force must the knee extensors exert to produce an angular acceleration at the knee of 1 rad/s2 , given a mass of the lower leg and foot of 4.5 kg, and a radius of gyration of 23 cm

Answer:

7.5 m/s².

Explanation:

From the question given above, the following data were:

Mass (m) of object = 0.6 Kg

Force of friction (Fբ) = 1.5 N

Acceleration (a) =?

Next, we shall determine the force of gravity on the object. This can be obtained as follow:

Mass (m) of object = 0.6 Kg

Acceleration due to gravity (g) = 10 m/s²

Force of gravity (F₉) =?

F₉ = mg

F₉ = 0.6 × 10

F₉ = 6 N

Next, we shall determine the net force acting on the object. This can be obtained as follow:

Force of friction (Fբ) = 1.5 N

Force of gravity (F₉) = 6 N

Net force (Fₙ) =?

Fₙ = F₉ – Fբ

Fₙ = 6 – 1.5

Fₙ = 4.5 N

Finally, we shall determine the acceleration of the object. This can be obtained as follow:

Mass (m) of object = 0.6 Kg

Net force (Fₙ) = 4.5 N

Acceleration (a) of object =?

Fₙ = ma

4.5 = 0.6 × a

Divide both side by 0.6

a = 4.5 / 0.6

a = 7.5 m/s²

Therefore, the acceleration of the object is 7.5 m/s²

Answer:

x-Speed/velocity

y-time.

Explanation:

because Speed is a rate of change of distance while time how long it takes a a car to move to a specific point

Answer:

533.33 nm

Explanation:

Since dsinθ = mλ  for each slit, where m = order of slit and λ = wavelength of light. Let m' = 10 th order fringe of the first slit of wavelength of light, λ = 640 nm and m"= 12 th order fringe of the second slight of wavelength of light, λ'.

Since the fringes coincide,

m'λ = m"λ'

λ' = m'λ/m"

= 10 × 640 nm/12

= 6400 nm/12

= 533.33 nm

Answer:

C. Sigmund Freud . . . Carl Jung

Explanation:

edge 2021

C.Sigmund Freud and Carl Jung both heavily relied on dream analysis in their treatment of patients.

Freud is well-known for inventing and developing the approach of psychoanalysis; for articulating the psychoanalytic idea of motivation, intellectual infection, and the structure of the unconscious; and for influencing medical and popular conceptions of human nature by using positing both everyday and strange thought.

Sigmund Freud was an Austrian neurologist who's perhaps maximum known as the founding father of psychoanalysis. Freud advanced a fixed of therapeutic strategies centered on communication therapy that worried the use of techniques that include transference, loose affiliation, and dream interpretation.

Learn more about Sigmund Freud here: https://brainly.com/question/2706543

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Answer:

35 N

Explanation:

F = ma

centripetal force = 10(3.5) = 35 N

Answer:

decomposition

Explanation:

Answer:

a. 3.81

Explanation:

F = GMm/r^2

F = (6.67 x 10^-11 x 28 x 1) / 7^2

F = 3.81 x 10^-11 N

Answer:

c.

Equal to 200 N..........

Explanation:

Heredity: The passing on of physical or mental characteristics genetically from one generation to another.

Dominant allele: In genetics, dominance is the phenomenon of one variant of a gene on a chromosome masking or overriding the effect of a different variant of the same gene on the other copy of the chromosome. The first variant is termed dominant and the second recessive.

Answer:

Heredity: the passing on of physical or mental characteristics genetically from one generation to another.

Dominant Allele: a variation of a gene that will produce a certain phenotype, even in the presence of other alleles.

Recessive Allele: a variety of genetic code that does not create a phenotype if a dominant allele is present.

Probablity: used to measure the chance or likelihood of an event to occur.

Genotype: an organism's complete set of genetic material

Phenotype: the set of observable characteristics of an individual resulting from the interaction of its genotype with the environment.

Answer:

the speed of the tip of a blade 10 s after the fan is turned off is 16.889 m/s.

Explanation:

Given;

diameter of the ceiling fan, d = 90 cm = 0.9 m

angular speed of the fan, ω = 64 rpm

time taken for the fan to stop, t = 28 s

The distance traveled by the ceiling fan when it comes to a stop is calculated as;

[tex]d = vt = \omega r\times t= ( \frac{64 \ rev}{\min} \times \frac{2 \pi \ rad}{rev} \times \frac{1 \min}{60 \ s} \times 0.9 \ m) \times 28 \ s\\\\d = 168.89 \ m[/tex]

The speed of the tip of a blade 10 s after the fan is turned off is calculated as;

[tex]v = \frac{d}{t} \\\\v = \frac{168.89}{10} \\\\v = 16.889 \ m/s[/tex]

Therefore, the speed of the tip of a blade 10 s after the fan is turned off is 16.889 m/s.

Explanation:

hi I like help but I couldn't

Answer:

1)   x = x₀ + vot - ½ c t² - 1/6 bt³,    v = v₀ - ct - ½ b t²

2)   v₁ = 5.25 m/s,         v₂ = -8 m/s

Explanation:

1) For this exercise, the relationship of the body is not constant, so you must use the definition of speed and position to find them.

acceleration is

           a = c + bt

a) the relationship between velocity and acceleration

           a = [tex]\frac{dv}{dt}[/tex]

           dv = -a dt

The negative sign is because the acceleration is contrary to the speed to stop the vehicle.

we integrate

           ∫ dv = - ∫ a dt

           ∫ dv = -∫ (c + bt) dt

            v = -c t - ½ b t²

This must be valued from the lower limit, the velocity is vo, up to the upper limit, the velocity is v for time t

             v - v₀ = -c (t-0) - ½ b (t²-0)

             v = v₀ - ct - ½ b t²

b) the velocity of the body is

             v = [tex]\frac{dx}{dt}[/tex]

             dx = v dt

we replace and integrate

              ∫ dx = ∫ (v₀ - c t - ½ bt²) dt

              x-x₀ = v₀ t - ½ c t² - ½ b ⅓ t³

Evaluations from the lower limit the body is at x₀ for t = 0 and the upper limit the body is x = x for t = t

           x - x₀ = v₀ (t-0) - ½ c (t²-0) + [tex]\frac{1}{6}[/tex]  (t³ -0)

           x = x₀ + vot - ½ c t² - 1/6 bt³

2) The speed when you reach the traffic light

Let's write the data that indicates, the initial velocity is vo = 15 m / s, the initial position is xo = 315m, let's use the initial values ​​to find the constants.

       t = 25 s x = 20

we substitute

          20 = 315 + 15 25 - ½ c 25² - 1/6 b 25³

         0 = 295 + 375 - 312.5 c - 2604.16 b

         670 = 312.5 c + 2604.16 b

we simplify

         2.144 = c + 8.33 b

Now let's use the equation for velocity,

        v = v₀ - ct - ½ b t²

        v = 15 - c 25 - ½ b 25²

        v = 15 - 25 c - 312.5 b

let's write our two equations

        2.144 = c + 8.33 b

        v = 15 - 25 c - 312.5 b

Let's examine our equations, we have two equations and three unknowns (b, c, v) for which the system cannot be solved without another equation, in the statement it is not clear, but the most common condition is that if the semaphore does not change, it follows with this acceleration (constant) to a stop

               a = c + b 25

from the first equation

              c = 8.33 / 2.144 b

              C = 3.885 b

we substitute in the other two

            v = 15 - 25 (3.885 b) - 312.5 b

            v = 15 - 409.6 b

final acelearation

            a = 28.885 b

let's use the cinematic equation

               [tex]v_{f}^2[/tex]= v² - 2 a x

                0 = v² - 2a 20

               0 = v² - (28.885b) 40

               v² = 1155.4 b

we write the system of equations

               v = 15 - 409.6 b

               v² = 1155.4 b

resolve

              v²= 1155.4 ( [tex]\frac{15 -v }{409.6}[/tex] )

              v² = 2.8 ( 15 -v)

              v² + 2.8 v - 42.3 = 0

              v=  [ -2.8 ±[tex]\sqrt {2.8^2 + 4 \ 42.3) }[/tex] ]/2 = [-2.8 ± 13.3]/2

              v₁ = 5.25 m/s

              v₂ = -8 m/s

The gravitational acceleration of a planet is proportional to the planet's mass, and inversely proportional to square of the planet's radius.

So when you stand on the surface of this particular planet, you feel a force of gravity that is

(1/2) / (3²)

of the force that you feel on the surface of the Earth.

That's (1/18) as much as on Earth.

The acceleration of gravity there would be about 0.545 m/s².  

This is about 12% less than the gravity on Pluto.

Answer:

(a) 8.85×10⁻³ minutes

(b) 4.24×10¹⁹ electrons

Explanation:

(a) Using,

Q = it............................. Equation 1

Where Q = quantity of charge, i = current, t = time.

Make t the subject of the equation

t = Q/i............................. Equation 2

Given: Q = 6.8×10⁰ C, i = 12.8 A

Substitute these values into equation 2

t = 6.8×10⁰/12.8

t = 8.85×10⁻³ minutes

(b) n = Q/(1.602×10⁻¹⁹)................. Equation 3

Where n = number of electrons.

Given: Q = 6.8×10⁰ C

Substitute into equation 2

n = 6.8×10⁰/1.602×10⁻¹⁹

n = 4.24×10¹⁹ electrons

(a) The time taken by the charge to flow from the drier will be [tex]\d8.85[/tex]×[tex]\d10^{-3}[/tex]minutes

(b) Amount of the electrons in the charge will be  [tex]\d4.24[/tex]×[tex]\d10^{19}[/tex] electrons

As we know Q = IT

Where Q = quantity of charge, i = current, T = time.

From the above equation

                    T= Q/I.

Given: Q = [tex]6.8\times\d10^{0}[/tex] C, i = 12.8 A

Substitute these values  

T=  [tex]6.8[/tex]×[tex]\d10^{0}[/tex] /12.8

T =  [tex]8.85[/tex]×[tex]\d10^{-3}[/tex] minutes

Now the number of the electrons present in the charge will be

n = Q/( [tex]1.602[/tex]×[tex]\d10^{-19}[/tex])

Where n = number of electrons.

Given: Q = [tex]6.8\times\d10^{0}[/tex] C

Substitute Value of Q  

n =  [tex]6.8\times\d10^{0}[/tex]/ [tex]1.602\times\d10^{-19}[/tex]

n = [tex]4.24\times\d10^{19}[/tex] electrons

Thus

(a)The time taken by the charge to flow from the drier will be [tex]\d8.85[/tex]×[tex]\d10^{-3}[/tex]minutes

(b)Amount of the electrons in the charge will be  [tex]\d4.24[/tex]×[tex]\d10^{19}[/tex] electrons

To know more about electric charge follow

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Answer: Mature red blood cells don't have nuclei.

Explanation: " Platelets are irregularly shaped, have no nucleus, and typically measure only 2–3 micrometers in diameter. "

Hope this Helps!!

Answer:

8.45 m

Explanation:

From the question given above, the following data were obtained:

Mass (m) = 90 Kg

Initial velocity (u) = 13 m/s

Final velocity (v) = 0 m/s

Height (h) =?

NOTE: Acceleration due to gravity (g) = 10 m/s²

The height of the hill can be obtained as follow:

v² = u² – 2gh (since the cart is going against gravity)

0² = 13² – (2 × 10 × h)

0 = 169 – 20h

Rearrange

20h = 169

Divide both side by 20

h = 169/20

h = 8.45 m

Therefore, the height of the hill is 8.45 m

Answer:

0.002 m/s

Explanation:

27.13(60) = 1,627.8 seconds

3.12/1,627.8 = 0.00191 ≈ 0.002 = s

Are you sure you're not looking for cm/s?

Answer:

The speed and direction of the third fragment are 2 meters per second and 54.316º, respectively.

Explanation:

The object is not under the influence of any external force, meaning that Principle of Momentum Conservation to calculation of the velocity of the third fragment:

[tex](m_{1}+m_{2}+m_{3})\cdot \vec {v}_{o} = m_{1}\cdot \vec v_{1} + m_{2}\cdot \vec v_{2} + m_{3}\cdot \vec v_{3}[/tex] (1)

Where:

[tex]m_{1}[/tex], [tex]m_{2}[/tex], [tex]m_{3}[/tex] - Masses of the first, second and third fragments, in kilograms.

[tex]\vec v_{o}[/tex] - Initial velocity of the object, in meters per second.

[tex]\vec v_{1}[/tex], [tex]\vec v_{2}[/tex], [tex]\vec v_{3}[/tex] - Velocities of the first, second and third fragments, in meters per second.

If we know that [tex]m_{1} = 0.5\,kg[/tex], [tex]m_{2} = 1.3\,kg[/tex], [tex]m_{3} = 1.2\,kg[/tex], [tex]\vec v_{o} = (0,0)\,\left[\frac{m}{s} \right][/tex], [tex]\vec v_{1} = \left(-2.8, 0\right)\,\left[\frac{m}{s} \right][/tex] and [tex]\vec v_{2} = \left(0,-1.5\right)\,\left[\frac{m}{s} \right][/tex], the velocity of the third fragment is:

[tex](-1.4,0) + (0,-1.95) + 1.2\cdot \vec v_{3} = (0,0)[/tex]

[tex]1.2\cdot \vec v_{3} = (1.4,1.95)[/tex]

[tex]\vec v_{3} = (1.167, 1.625)\,\left[\frac{m}{s} \right][/tex]

The speed of the third fragment is the magnitude of the result found above:

[tex]v_{3} = 2\,\frac{m}{s}[/tex]

And the direction of the third fragment is:

[tex]\theta_{3} = \tan^{-1} \left(\frac{1.625}{1.167}\right)[/tex]

[tex]\theta_{3} \approx 54.316^{\circ}[/tex]

The speed and direction of the third fragment are 2 meters per second and 54.316º, respectively.

Answer:

the motorcycle travels 522 miles in 18 seconds Explanation: 29 x 18 is 522 I'm pretty sure that's what it was asking but I don't know

Answer:

The respiratory system provides oxygen for cells, while the circulatory system transports oxygen to cells.

Explanation:

so the answer is D

Answer:

I = 2387.32 A

Explanation:

Given that,

Number of turns in the loop, N = 400

The radius of the circular coil, r = 0.66 m

The magnetic field inside the MRI, B = 1.2 T

We need to find the current in the loop. The magnetic field inside the solenoid is given by :

[tex]B=\mu_o NI\\\\I=\dfrac{B}{\mu_o N}\\\\I=\dfrac{1.2}{4\pi \times 10^{-7}\times 400}\\\\I=2387.32\ A[/tex]

So, the required current is equal to 2387.32 A.

Answer:

correct tysmm

Explanation:

Answer:

e. the number of active motor units increases.

Explanation:

There is a direct relationship between the number of active motor units and the grip strength in a given scenario. For example, increase in the grip strength leads to increase in the number of active motor units. In the other-hand, the decrease in grip strength leads to the decrease in the number of active motor units.

Answer:

average speed of the fist during the hook = 15 m/s or 1500 cm/s

Explanation:

We are given;

Speed of shoulder contraction, v_s = 75 cm/s = 0.75 m/s

Distance moved through the arc length by shoulder, d_s = 5 cm = 0.05 m

Distance moved by the fist, d_f = 100 cm = 1 m

Now, we are to find the average speed of the fist during the hook; v_f

Thus can be gotten from proportion;.

d_f/d_s = v_f/ v_s

Making V_f the subject, we have;

v_f = (d_f × v_s)/d_s

Thus;

v_f = (1 × 0.75)/0.05

v_f = 0.75/0.05

v_f = 15 m/s

Answer:

50 protons 50 electrons and 69 neutrons...

Explanation:

the number of protons is equal to number of electrons. then mass number is the sum of protons and neutrons in a nucleus so for we to get the number of neutrons we take the mass number subtract the protons number.

Answer:

In metals there are free electrons at normal temperature so when we increase temperature it resistivity gets increases,so conductivity decreases,while in semiconductor the electrons are not free so when we increase the temperature the covalent bonds begin to break and the electron becomes free so conductivity get.

Explanation: