please answer True or false

In two square the server earns a point when the opponent catches the ball.​

Answer:

The magnitudes of the speed and acceleration of the Earth are approximately 66,661.217 miles per hour and 47.782 miles per square hour, respectively.

Explanation:

Given that the Earth has a circular orbit and make a revolution at constant speed around the Sun. Then, the kinematic formulas for the speed and acceleration of the planet are, respectively:

Speed

[tex]v = \frac{2\pi\cdot R}{T}[/tex] (1)

Acceleration

[tex]a = \frac{4\pi^{2}\cdot R}{T^{2}}[/tex] (2)

Where:

[tex]v[/tex] - Speed of the planet, measured in miles per hour.

[tex]a[/tex] - Acceleration of the planet, measured in miles per square hour.

[tex]R[/tex] - Radius of the orbit, measured in miles.

[tex]T[/tex] - Period of rotation, measured in hours.

If we know that [tex]R = 93,000,000\,mi[/tex] and [tex]T = 8,765.76\,h[/tex], then the magnitudes of the speed and acceleration of the planet is:

[tex]v = \frac{2\pi\cdot (93,000,000\,mi)}{8,765.76\,h}[/tex]

[tex]v \approx 66,661.217\,\frac{mi}{h}[/tex]

[tex]a = \frac{4\pi^{2}\cdot (93,000,000\,mi)}{(8,765.76\,h)^{2}}[/tex]

[tex]a\approx 47.782\,\frac{mi}{h^{2}}[/tex]

The magnitudes of the speed and acceleration of the Earth are approximately 66,661.217 miles per hour and 47.782 miles per square hour, respectively.

Answer:

1. False

2. Fats

3. False

Explanation:

MyPlate is an initiative from the United States Department of Agriculture that is designed to help Americans improve their eating habits throughout their lifetimes. Every meal matters. The five food groups represented in My Plate include vegetables, grain, dairy, protein foods, and fruits.

Calories are a source of energy for the human body. So, the more active a person is, the more energy he would need to be supplied to him in form of calories. The less active a person is, the fewer calories he would need.

Answer:

52,163.1

Explanation:

Answer:

The longest wavelength of light needed to produce current is 567.9 nm.

Explanation:

Given;

minimum energy required to produce electric current from the cathode to anode = work function, E = 3.5 x 10⁻¹⁹ J

E = hf

[tex]E = \frac{hc}{\lambda}[/tex]

where;

c is speed of light = 3 x 10⁸ m/s

λ is the longest wavelength of light needed to produce current

[tex]E = \frac{hc}{\lambda} \\\\\lambda = \frac{hc}{E} \\\\\lambda = \frac{(6.626\times 10^{-34})(3\times 10^8)}{3.5\times 10^{-19}}\\\\\lambda = 5.679 \times 10^{-7} \ m\\\\\lambda = 567.9 \times 10^{-9} \ m\\\\\lambda = 567.9 \ nm[/tex]

Therefore, the longest wavelength of light needed to produce current is 567.9 nm.

Answer:

The answer is "wedge​"

Explanation:

A wedge is an item that tightens to a meager edge. Pushing the wedge one direction makes a force in a sideways direction. It is normally made of metal or wood and is used for parting, tightening, lifting, or fixing, as in making sure about a hammer head onto its handle.

The wedge was used in ancient occasions to part logs and shakes; an ax is also a wedge, similar to the teeth on a saw. As far as its mechanical capacity, the screw might be considered as a wedge folded over a cylinder.

Answer:

The second one I think

Explanation:

B

Answer:

The value is [tex]R_f = \frac{4}{5} R[/tex]

Explanation:

From the question we are told that

   The  initial velocity of the  proton is [tex]v_o[/tex]

    At a distance R from the nucleus the velocity is  [tex]v_1 = \frac{1}{2} v_o[/tex]

    The  velocity considered is  [tex]v_2 = \frac{1}{4} v_o[/tex]

Generally considering from initial position to a position of  distance R  from the nucleus

 Generally from the law of energy conservation we have that  

       [tex]\Delta K = \Delta P[/tex]

Here [tex]\Delta K[/tex] is the change in kinetic energy from initial position to a  position of  distance R  from the nucleus , this is mathematically represented as

      [tex]\Delta K = K__{R}} - K_i[/tex]

=>    [tex]\Delta K = \frac{1}{2} * m * v_1^2 - \frac{1}{2} * m * v_o^2[/tex]

=>    [tex]\Delta K = \frac{1}{2} * m * (\frac{1}{2} * v_o )^2 - \frac{1}{2} * m * v_o^2[/tex]

=>    [tex]\Delta K = \frac{1}{2} * m * \frac{1}{4} * v_o ^2 - \frac{1}{2} * m * v_o^2[/tex]

And  [tex]\Delta P[/tex] is the change in electric potential energy  from initial position to a  position of  distance R  from the nucleus , this is mathematically represented as

          [tex]\Delta P = P_f - P_i[/tex]

Here  [tex]P_i[/tex] is zero because the electric potential energy at the initial stage is  zero  so

             [tex]\Delta P = k * \frac{q_1 * q_2 }{R} - 0[/tex]

So

           [tex]\frac{1}{2} * m * \frac{1}{4} * v_o ^2 - \frac{1}{2} * m * v_o^2 = k * \frac{q_1 * q_2 }{R} - 0[/tex]

=>        [tex]\frac{1}{2} * m *v_0^2 [ \frac{1}{4} -1 ] = k * \frac{q_1 * q_2 }{R}[/tex]

=>        [tex]- \frac{3}{8} * m *v_0^2 = k * \frac{q_1 * q_2 }{R} ---(1 )[/tex]

Generally considering from initial position to a position of  distance [tex]R_f[/tex]  from the nucleus

Here [tex]R_f[/tex] represented the distance of the proton from the nucleus where the velocity is  [tex]\frac{1}{4} v_o[/tex]

     Generally from the law of energy conservation we have that  

       [tex]\Delta K_f = \Delta P_f[/tex]

Here [tex]\Delta K[/tex] is the change in kinetic energy from initial position to a  position of  distance R  from the nucleus  , this is mathematically represented as

      [tex]\Delta K_f = K_f - K_i[/tex]

=>    [tex]\Delta K_f = \frac{1}{2} * m * v_2^2 - \frac{1}{2} * m * v_o^2[/tex]

=>    [tex]\Delta K_f = \frac{1}{2} * m * (\frac{1}{4} * v_o )^2 - \frac{1}{2} * m * v_o^2[/tex]

=>    [tex]\Delta K_f = \frac{1}{2} * m * \frac{1}{16} * v_o ^2 - \frac{1}{2} * m * v_o^2[/tex]

And  [tex]\Delta P[/tex] is the change in electric potential energy  from initial position to a  position of  distance [tex]R_f[/tex]  from the nucleus , this is mathematically represented as

          [tex]\Delta P_f = P_f - P_i[/tex]

Here  [tex]P_i[/tex] is zero because the electric potential energy at the initial stage is  zero  so

             [tex]\Delta P_f = k * \frac{q_1 * q_2 }{R_f } - 0[/tex]      

So

          [tex]\frac{1}{2} * m * \frac{1}{8} * v_o ^2 - \frac{1}{2} * m * v_o^2 = k * \frac{q_1 * q_2 }{R_f }[/tex]

=>        [tex]\frac{1}{2} * m *v_o^2 [-\frac{15}{16} ] = k * \frac{q_1 * q_2 }{R_f }[/tex]

=>        [tex]- \frac{15}{32} * m *v_o^2 = k * \frac{q_1 * q_2 }{R_f } ---(2)[/tex]

Divide equation 2  by equation 1

              [tex]\frac{- \frac{15}{32} * m *v_o^2 }{- \frac{3}{8} * m *v_0^2 } } = \frac{k * \frac{q_1 * q_2 }{R_f } }{k * \frac{q_1 * q_2 }{R } }}[/tex]

=>           [tex]-\frac{15}{32 } * -\frac{8}{3} = \frac{R}{R_f}[/tex]

=>           [tex]\frac{5}{4} = \frac{R}{R_f}[/tex]

=>             [tex]R_f = \frac{4}{5} R[/tex]

Answer:

Capital (G) is a universal gravitation law. and small (g) is acceleration of gravity of the each (9.8m/s^2)

Explanation:

According to the web

Answer:

The value is  [tex]\theta = 16.38^o[/tex]

Explanation:

From the question we are told that

    The  radius is  [tex]r = 50 \ m[/tex]

    The  velocity is  [tex]v = 12 \ m/s[/tex]

Generally the angle is mathematically represented as

          [tex]\theta = tan^{-1} [\frac{v^2}{ gr} ][/tex]

=>       [tex]\theta = tan^{-1} [\frac{12^2}{ 9.8 * 50 } ][/tex]

=>       [tex]\theta = tan^{-1} [ 0.2939 ][/tex]

=>        [tex]\theta = 16.38^o[/tex]

Answer:

58.56 J

Explanation:

Since the formula for gravitational potential energy is:

GE = m x g x h - where m = mass (kg), g = acceleration due to gravity (9.81 m/s²), h = height (m)

GE= 3 x 9.81 x 2

GE = 58.86 J

Hope this helps

Answer:

satellite technology helped large ocean liners guide you to our space mission.

Explanation:

Large ocean liners use satellites to aid in navigation. This type of navigation aid is also used on cruise ships. Using satellites can help these large ships navigate waters during bad storms.

Satellite surveillance can be used to aid in port security. Satellite data can be monitored and evaluated by complex computer systems. These systems can alert officials when something unusual occurs.

Satellite technology allows us to monitor and track the changes in the polar ice sheets. This can help us plan and direct conservation efforts for the animals that depend on polar ice in order to survive.

Satellite surveillance has allowed us to map areas that were previously too remote to observe. This helps developers to locate and choose sites for large resorts.

Answer:

Positively Charge formation on the electroscope pulls the electrons so no emission happens.

Explanation:

Photoelectric effect is the process by which the electrons get ejected when light of certain frequency falls on the material. The energy from the electromagnetic radiation excites the electron by providing it enough energy as a result it gets ejected.

The Ultraviolet(UV) light is a form of electromagnetic radiation, If the UV radiation strikes an uncharged electroscope, it is predicted that it will cause the electrons in the electroscope to excite and to be emitted.  But on the contrary no noticeable effect is observed on the electroscope this happened because when UV light makes the electroscope positively(+) charged this creates a pull for the electrons, as a result rather emitting the electrons gets pulled by the positively charged electroscope.

Therefore the positively charge formation on the electroscope hinder the electrons emission and there is no noticeable effect.  

Answer:

The value is  [tex]\alpha = 3.84 \ rad/s^2[/tex]

Explanation:

From the question we are told that

    The constant angular speed is  [tex]w = 11.9 \ rad/s[/tex]

     The time taken is  [tex]t = 3.10 \ s[/tex]

Generally the magnitude of the angular acceleration is  mathematically represented as  

          [tex]\alpha = \frac{w}{t}[/tex]

=>     [tex]\alpha = \frac{11.9}{ 3.10 }[/tex]

=>     [tex]\alpha = 3.84 \ rad/s^2[/tex]

Answer:

1.1x10^-2N

Explanation:

We have the change in momentum as

P = 0.3(4.5+12)g.mph

= 0.3x0.447x(4.5+12)x10^-3

Then the force that is exerted will be

F = p/∆t

∆t = 0.2

= 0.3x0.447x(4.5+12)x10^-3/0.2

= 0.1341x16.5x10^-3/0.2

= 1.1x10^-2

Therefore the force that was exerted is equal to 1.1x10^-2

The required magnitude of the force exerted on the fly is of [tex]5.025 \times 10^{-3} \;\rm N[/tex].

Given data:

The mass of mosquito is, [tex]m =0.3 \;\rm g =3 \times 10^{-4} \;\rm kg[/tex]

The speed of flying is, u = 4.5 mph = 4.5 ( 0.447) = 2.01 m/s.

The swatting speed of mosquito is, v = 12 mph = 12 (0.447 ) = 5.36 m/s.

The time of contact is, t = 0.2 s.

In this problem, we will first calculate the change in momentum, and the change in momentum is given as,

p = m ( v - u)

Solving as,

[tex]p = 3 \times 10^{-4} (5.36 - 2.01)\\\\p = 1.005 \times 10^{-3} \;\rm kg.m/s[/tex]

Now as per the Newton's second law,

[tex]F = p/t\\\\F = 1.005 \times 10^{-3} / 0.2\\\\F= 5.025 \times 10^{-3} \;\rm N[/tex]

Thus, the required magnitude of the force exerted on the fly is of [tex]5.025 \times 10^{-3} \;\rm N[/tex].

Learn more about the Newton's second law here:

https://brainly.com/question/19860811

Answer:

B. Density

Explanation:

Thermal expansion of a gas will cause a definite change in the density of the gas.

It is product of an increase in the average kinetic energy of the system in which molecules are found.

Therefore, thermal expansion of gas will cause a change in the density of the gas.

Work done by lifting is 3,300 Newton.

Given that;

Mass of thing = 15 kg

Height lifted = 22 m

Find:

Work done by lifting

Computation:

Work done = mgh

Work done by lifting = (15)(10)(22)

Work done by lifting = 3,300 Newton

Learn more:

https://brainly.com/question/14729868?referrer=searchResults

We are given:

Frequency of the wave = 100 Hz

Velocity of the wave = 5 m/s

Finding the Wavelength:

We know the relation between the wavelength and frequency is:

u = νλ    [where ν is the frequency, u is the speed and λ is the wavelength]

5 = 100*(λ)

λ = 5/100         [dividing both sides by 100]

λ = 1/20

λ = 0.05 m

Hence, the wavelength is 0.05 m

Answer:

93.125 × 10^(19)

Explanation:

We are told the asteroid has acquired a net negative charge of 149 C.

Thus;

Q = -149 C

charge on electron has a value of:

e = -1.6 × 10^(-19) C

Now, for us to determine the excess electrons on the asteroid, we will just divide the net charge in excess on the asteroid by the charge of a single electron.

Thus;

n = Q/e

n = -149/(-1.6 × 10^(-19))

n = 93.125 × 10^(19)

Thus, it has 93.125 × 10^(19) more electrons than protons

Answer: a. nuclear fission.

Explanation:

Nuclear power plants use heavy materials, like uranium 238, which is bombarded with neutrons. When the neutrons interact with the uranium, there is fission (a division of one atom into smaller ones and other subatomic particles), and in this process, more neutrons are produced. These new neutrons may impact other atoms of uranium and continue with this cycle, generating heat in the process.

Then we can conclude that nuclear power plants produce energy using nuclear fission.

Complete Question

Suppose a wireless charging system of an electric toothbrush. The charger has Solenoid 1 with 800 turns and the toothbrush has Solenoid 2 with 150 turns. The current in the charger is 220 mA and the corresponding average magnetic flux through Solenoid 2 is 0.056 Wb. What is the mutual inductance of the pair of the solenoids?

Answer:

The value is [tex]M = 38.2 \ H[/tex]

Explanation:

From the question we are told that

     The number of turns of solenoid 1 is [tex]N_1 = 800[/tex]

     The  number of turns for solenoid 2 is  [tex]N_2 = 150 \ turns[/tex]

     The current in the charger is  [tex]I = 220 \ mA = 220 *10^{-3} \ A[/tex]

      The  magnetic flux through solenoid 2 is  [tex]\phi = 0.056 \ Wb[/tex]

Generally mutual inductance is mathematically represented as

        [tex]M = \frac{N_2 * \phi }{ I }[/tex]

=>     [tex]M = \frac{150 * 0.056 }{ 220 *10^{-3} }[/tex]

=>    [tex]M = 38.2 \ H[/tex]

Given :

The mass of the balloon was 1890 kg and had a volume of 11,430 m3 .

The balloon floats at a constant height of 6.25m above the ground.

To Find :

The density of the hot air in the balloon.

Solution :

We know,

Volume × ( Density of surrounding air - Density of hot air ) = mass

Putting given values in above equation, we get :

[tex]11430\times ( 1.29 - \rho_{hot \ air } ) = 1890\\\\\rho_{hot \ air } = 1.29 - \dfrac{1890}{11430}\\\\\rho_{hot \ air } = 1.125\ kg\ m^3[/tex]

Therefore, the density of hot air in the balloon is 1.125 kg m³.

Answer:

Object's kinetic energy is high on frictionless medium.

Explanation:

There is a great difference in object's kinetic energy which is present between sliding with friction and sliding without friction because friction decreases the speed of an object so if an object moves on the frictionless medium, it moves and covers more distance and we can say that the object has more kinetic energy while on the other hand, if a body moves on the medium and experience friction so it moves with little speed so we can say that the body has low kinetic energy.

Answer:

the answer is b mark me as the brqinlist

Answer:

C; Rowing a boat

Explanation:

Hope this helps!      :3

Plz mark as brainliest!

Answer: the angle between the resultant vector and the vector of the 18 pound is 28°

Explanation:

given that data in the question; as its interpreted in the diagram below;

from the cosine rule, we know that;

a² = b² + c² - 2bc  

so

(13)² = (6)² + (18)² - (2 × 6 × 18 ) cos∅

169 = 36 + 324 - 216cos∅

169 = 360 - 216cos∅

216cos∅ = 360 - 169

216cos∅ = 191

cos∅ = 0.8842

∅ = cos⁻¹ ( 0.8842 )

∅ = 27.8° ≈ 28°  {nearest whole number}

Therefore the angle between the resultant vector and the vector of the 18 pound is 28°

Answer:

2.92 m/s

Explanation:

For the entire motion, the average velocity (V) can be calculated thus;

V = [tex]\frac{displacement}{time}[/tex]

Total displacement of the player = 10.0 + (-5) + 17.2

        = 22.2 m

Total time = 2.00 + 1.50 + 4.10

         = 7.60 s

V = 22.2/7.60

       = 2.92 m/s

Hence, the velocity of the players for the entire motion is 2.92 m/s.