A good soccer player can kick the ball up to 25 m/sec. A soccer ball has a mass of 800 grams (0.8 kg). What force must a goalie exert on the ball to bring it to rest in 0.1 sec?

Answer:

b. 200N c. 100N

Explanation:

30.

the horizontal. The force needed to push the body up the plane is

Answer:

* angular momentum throughout the lar process is conserved throughout the entire process

* the angular velocity decreases as the radius of the pizza increases

Explanation:

The system formed by the masses is isolated so its angular momentum is conserved

  initial instant, which throws the mass with angular velocity o and radius ro

           L₀ = I w₀

final instant. When the mass has a radius r and an angular velocity w

           L_f = I_f w

           Lo = l_f

           I₀ w₀ = I_f w_f

           [tex]\frac{ w_f}{w_o } } = \frac{r_o}{r_f}[/tex]

let's analyze this result

* angular momentum throughout the lar process is conserved throughout the entire process

* the angular velocity decreases as the radius of the pizza increases

Answer:

13.09 s

Explanation:

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

Power (P) = 275 W

Work (W) = 3600 J

Time (t) =?

Power is defined as the rate at which work is done. Mathematically, it can be expressed:

Power (P) = Work (W) / time (t)

P = W/t

With the above formula, we can obtain the time taken for the swimmer to accomplish the work. This can be obtained as follow:

Power (P) = 275 W

Work (W) = 3600 J

Time (t) =?

P = W/t

275 = 3600/t

Cross multiply

275 × t = 3600

Divide both side by 275

t = 3600 / 275

t = 13.09 s

Thus, it will take the swimmer 13.09 s to accomplish the work.

Answer:

[tex]12.35\:\mathrm{m/s}[/tex]

Explanation:

We can use the work-energy theorem to solve this problem. The work-energy theorem states that the work done on an object will be equal to that object's change in kinetic energy. Thus, we have the following equation:

[tex]W=\Delta KE,\\W=\frac{1}{2}mv^2-0,\\122=\frac{1}{2}\cdot 1.6\cdot v^2,\\v^2=152.5,\\v\approx \boxed{12.35\:\mathrm{m/s}}[/tex]

Answer:

False

Explanation:

The alpha decay or alpha radiation is one type of radioactive decay. What is emitted is an alpha particle which is helium nucleus and not the hydrogen nucleus. The alpha particle is made up of two protons as well as two neutrons. This is the helium nucleus.

Therefore the right answer to this question is false.

Answer:

potential energy is a form of energy that a body possess to its position.Potential energy is equal to potential energy is equal to mass times acceleration due to gravity times height.

Answer: 48,000 J

Explanation: i just did it

Answer: [tex]115.52\ N[/tex]

Explanation:

Given

Length of plank is 1.6 m

Force [tex]F_1[/tex] is applied on the left side of plank

Force [tex]F_2[/tex] is applied 43 cm from the left end O.

Mass of the plank is [tex]m=13.7\ kg[/tex]

for equilibrium

Net torque must be zero. Taking torque about left side of the plank

[tex]\Rightarrow mg\times 0.8-F_2\times 0.43=0\\\\\Rightarrow F_2=\dfrac{13.7\times 9.8\times 0.8}{0.43}\\\\\Rightarrow F_2=249.78\ N[/tex]

Net vertical force must be zero on the plank

[tex]\Rightarrow F_1+W-F_2=0\\\Rightarrow F_1=F_2-W\\\Rightarrow F_1=249.78-13.7\times 9.8\\\Rightarrow F_1=115.52\ N[/tex]

Answer:

[tex]11616ft^{2}[/tex] or 11616

Explanation:

Since there are 5280 feet in 1 mile

you do 2.2 × 5280

2.2 × 5280 = 11616

Answer:

B, the internet serves to provide people with more insightful explanations on things that they have not experienced yet but want to find out more on.

Momentum = (mass) x (speed)

If you work the problem in the same units as the given data, then you get the momentum in units of kilogram-meters per second, and your horse has 1,440 of them.

Answer:

A

Explanation:

1440 kg*m/s

Thermal energy is transferred by [tex]\sf\purple{conduction}[/tex] when objects touch.

3. Conduction ✔

[tex]\circ \: \: { \underline{ \boxed{ \sf{ \color{green}{Happy\:learning.}}}}}∘[/tex]

Answer:

the speed of the first spacecraft as viewed from the second spacecraft is 0.95c

Explanation:

Given that;

speed of the first spacecraft from earth v[tex]_a[/tex] = 0.80c

speed of the second spacecraft from earth v[tex]_b[/tex] = -0.60 c

Using the formula for relative motion in relativistic mechanics

u' = ( v[tex]_a[/tex] - v[tex]_b[/tex] ) / ( 1 - (v[tex]_b[/tex]v[tex]_a[/tex] / c²) )

we substitute

u' = ( 0.80c - ( -0.60c)  ) / ( 1 - ( ( 0.80c × -0.60c) / c² ) )

u' = ( 0.80c + 0.60c ) /  ( 1 - ( -0.48c² / c² ) )

u' = 1.4c /  ( 1 - ( -0.48 ) )

u' = 1.4c /  ( 1 + 0.48 )

u' = 1.4c / 1.48

u' = 0.9459c ≈ 0.95c  { two decimal places }

Therefore, the speed of the first spacecraft as viewed from the second spacecraft is 0.95c

Answer:

t = 4.08 s

Explanation:

if the body is thrown upward, it has negative gravity. Knowing through the International System that the earth's gravity is 9.8 m/s²

Data:

Use formula:

Replace and solve:

Time taken by it to reach max height is 4.08 seconds.

Greetings.

Answer:

(a) I = 1650000 A

(b) 4.125 T

Explanation:

Magnetic field, B = 5.5 T

distance, r = 0.06 m

(a) Let the current is I.

The magnetic field due to a long wire is given by

[tex]B =\frac{\mu o}{4\pi }\frac{2 I}{r}\\5.5= 10^{-7}\times \frac{2\times I}{0.06}\\I =1650000 A[/tex]

(b) Let the magnetic field is B' at distance r = 0.08 m.

[tex]B =\frac{\mu o}{4\pi }\frac{2 I}{r}\\B = 10^{-7}\times \frac{2\times 1650000}{0.08}\\B'= 4.125 T[/tex]

Answer:

[tex]v_{0,new} = v0\sqrt{}2[/tex]

Explanation:

Initial work done on the proton is given by, [tex]\DeltaW0 = q V_o[/tex]

we know that, [tex]\DeltaW = \DeltaK.E[/tex]

[tex]qV0 = (1/2) m v_0^2[/tex]

[tex]v_0 = \sqrt{}2 q V_0 / m[/tex]                                                        { eq.1 }

If it were accelerated instead through a potential difference of 2V0, then it would gain a speed will be given as :

using the above formula, we have

[tex]v_{0,new} = \sqrt{}2 q (2V0) / m[/tex]    

[tex]v_{0,new} = \sqrt{}4 q V0 / m[/tex]    

[tex]v_{0,new} = v0\sqrt{}2[/tex]

Answer:

None of the above forces on air drag on him is equal to his weight

Explanation:

In the velocity-time graph,the gradient of the curve where it is flatten shows the parachutist reaches the terminal velocity when it reaches terminal velocity which means the parachutist reaches constant velocity or speed,indicating that the acceleration of free fall(g) is zero.And according to the resultant force formula weight - air drag= mass*acceleration. so when accelerate is zero,resultant force is zero. And hence the equation will be like this: weight= air drag

Answer:

Russia is the largest country in the world covering more than 6.6 million square miles. ... Russia also spreads across two continents, covering a portion of Eastern Europe that borders the Ural Mountains. 4. The country's official name is the Russian Federation.

Answer:

10 Things to Know About Russia

The world's largest country has the longest railway, second-largest art museum in the world and is home to many billionaires.

Russia is the world's largest nation with a rich history and several dozen ethnic groups. Its history is dominated by invasions, monarchies and a the authoritarian 20th-century Soviet regime. Its current politicians are often at odds with Western values and clash with both Europe and the United States.

Here are 10 interesting facts about Russia.

1. Russia is the largest country in the world covering more than 6.6 million square miles.

2. It is located in the Northern Hemisphere and borders two oceans -- the Arctic Ocean and the North Pacific Ocean.

3. Russia also spreads across two continents, covering a portion of Eastern Europe that borders the Ural Mountains.

4. The country's official name is the Russian Federation.

5. The median age for Russia's population is 39.6 years old. There are about 140 million residents in the country as of 2017.

6. Russia's capital city Moscow is one of the wealthiest cities in the world by the number of billionaires. In 2018, the city reported 69 billionaires, after New York, Hong Kong and San Francisco.

7. Also in Moscow there is a restaurant staffed only with twins, called the Twin Stars.

8. The second-largest art museum in the world, the Hermitage, is located in Russia's former capital, Saint Petersburg. The museum has more than 3 million art pieces.

9. The deepest lake in the world (deeper than 5,000 feet), Lake Baikal, is located in Siberia.

10. The best known train route in Russia is the Trans-Siberian railway, the world's longest railway, connecting Moscow to Vladivostok. Yet there are several other scenic train routes that connect the capital to Beijing via Mongolia or Manchuria.

Answer:

its number 2 one but i am not sure hope its right

Answer:

[tex]P_a=17.85psi[/tex]

Explanation:

From the question we are told that:

Tank Pressure [tex]P_t=30.0kpa[/tex]

Atmospheric Pressure [tex]P_a=13.5 psi[/tex]

Where

 [tex]1kpa=0.148psi[/tex]

Therefore

 [tex]30kpa=4.35psi[/tex]

Generally the equation for Absolute pressure [tex]P_a[/tex] is mathematically given by

 [tex]P_a=13.5+4.35[/tex]

 [tex]P_a=17.85psi[/tex]

The question is incomplete. The complete question is :

A long, straight wire lies along the z-axis and carries a 3.90-A current in the + z-direction. Find the magnetic field (magnitude and direction) produced at the following points by a 0.600 mm segment of the wire centered at the origin.

A) x=2.00m,y=0, z=0

Bx,By,Bz = ? T

Enter your answers numerically separated by commas.

B) x=0, y=2.00m, z=0

C) x=2.00m, y=2.00m, z=0

D) x=0, y=0, z=2.00m

Solution :

The expression of the magnetic field using the Biot Savart's law is given by :

[tex]$d \vec B=\frac{\mu_0 I\vec{dl} \times \vec r}{4 \pi r^3}$[/tex]

a). The position vector is on the positive x direction.

[tex]$\vec r = (2 \ m) \ \hat i$[/tex]

[tex]$|r| = 2 \ m$[/tex]

The magnetic field is  

[tex]$d \vec B=\frac{\mu_0 I\vec{dl} \times \vec r}{4 \pi r^3}$[/tex]

[tex]$d \vec B=\frac{4 \pi \times 10^{-7} \times 3.9 \times 0.6 \times 10^{-3} \times\hat k \times (2 ) \hat i }{4 \pi \times (2)^3}$[/tex]

[tex]$d \vec B=(5.85 \times 10^{-11} \ T)\hat j$[/tex]

The magnetic field is   [tex]$(0, \ 5.85 \times 10^{-11} \ T, \ 0).$[/tex]

b). The position vector is in the positive y-direction.

[tex]$\vec r = (2 \ m) \ \hat j$[/tex]

[tex]$|r| = 2 \ m$[/tex]

The magnetic field is

[tex]$d \vec B=\frac{\mu_0 I\vec{dl} \times \vec r}{4 \pi r^3}$[/tex]

[tex]$d \vec B=\frac{4 \pi \times 10^{-7} \times 3.9 \times 0.6 \times 10^{-3} \times\hat k \times (2 ) \hat j }{4 \pi \times (2)^3}$[/tex]

[tex]$d \vec B=(5.85 \times 10^{-11} \ T)(-\hat{i})$[/tex]

The magnetic field is   [tex]$(- 5.85 \times 10^{-11} \ T, \ 0, \ 0).$[/tex]

c). The position vector is :

[tex]$\vec r = (2)\hat i + (2)\hat j$[/tex]

[tex]$|\vec r| = \sqrt{(2)^2+(2)^2}$[/tex]

   [tex]$=2.828 \ m$[/tex]

The magnetic field is

[tex]$d \vec B=\frac{\mu_0 I\vec{dl} \times \vec r}{4 \pi r^3}$[/tex]

[tex]$d \vec B=\frac{4 \pi \times 10^{-7} \times 3.9 \times 0.6 \times 10^{-3} \times\hat k \times ((2)\hat i + (2) \hat j) }{4 \pi \times (2.828)^3}$[/tex]

   [tex]$=(4.13\times 10^{-11})\hat j+(4.13\times 10^{-11})(-\hat i)$[/tex]

The magnitude of the magnetic field is :

[tex]$|d\vec B|=\sqrt{(4.13\times 10^{-11})^2+(4.13\times 10^{-11})^2}$[/tex]

       [tex]$=5.84 \times 10^{-11} \ T$[/tex]

Therefore, the magnetic field is [tex]$(-4.13 \times 10^{-11}\ T, \ 4.13 \times 10^{-11}\ T, \ 0 )$[/tex]

d).  The position vector is in the positive y-direction.

[tex]$\vec r = (2 \ m) \ \hat k$[/tex]

[tex]$|r| = 2 \ m$[/tex]

The magnetic field is

[tex]$d \vec B=\frac{\mu_0 I\vec{dl} \times \vec r}{4 \pi r^3}$[/tex]

[tex]$d \vec B=\frac{4 \pi \times 10^{-7} \times 3.9 \times 0.6 \times 10^{-3} \times\hat k \times (2 ) \hat k }{4 \pi \times (2)^3}$[/tex]

   = 0 T

The magnetic field is (0, 0, 0)

Answer:

a) the wavelength that the light emits is 6.1875 × 10⁻⁷ m

b) the distance between the two n = 1 dark fringes is 5.5 × 10⁻³ m

Explanation:

Given the data in the question;

separation  between two slits  d = 0.36 mm = 0.00036 m

Separation between two adjacent fringes β = 5.5 mm = 0.0055 m

Distance of screen from slits D = 1.6 m

n = 2

a) the wavelength the light emits;

Using the formula;

β = (nD/d)λ

To find wavelength, we make λ the subject of formula;

βd = nDλ

λ = βd / nD

so we substitute

λ = ( 0.0055 m × 0.00036 m ) / ( 2 × 1.6 m )

λ = 0.00000198 / 3.2

λ = 6.1875 × 10⁻⁷ m

Therefore, the wavelength that the light emits is 6.1875 × 10⁻⁷ m

b) the distance between the two n = 1 dark fringes;

To find the distance between the two n = 1 dark fringes, we use the following formula;

y[tex]_m[/tex] = 2nλD / d

given that n = 1, we substitute

y[tex]_m[/tex] = ( 2 × 1 × ( 6.1875 × 10⁻⁷ m ) × 1.6 m ) / 0.00036 m

y[tex]_m[/tex] = 0.00000198 / 0.00036

y[tex]_m[/tex] = 0.0055 m

y[tex]_m[/tex] = 5.5 × 10⁻³ m

Therefore, the distance between the two n = 1 dark fringes is 5.5 × 10⁻³ m

Complete question:

while hunting in a cave a bat emits sounds wave of frequency 39 kilo hartz were moving towards a wall with a constant velocity of 8.32 meters per second take the speed of sound as 340 meters per second. calculate the frequency​ reflected off the wall to the bat?

Answer:

The frequency reflected by the stationary wall to the bat is 41 kHz

Explanation:

Given;

frequency emitted by the bat, = 39 kHz

velocity of the bat, [tex]v_b[/tex] = 8.32 m/s

speed of sound in air, v = 340 m/s

The apparent frequency of sound striking the wall is calculated as;

[tex]f' = f(\frac{v}{v- v_b} )\\\\f' = 39,000(\frac{340}{340 -8.32} )\\\\f' = 39978.29 \ Hz[/tex]

The frequency reflected by the stationary wall to the bat is calculated as;

[tex]f_s = f'(\frac{v + v_b}{v} )\\\\f_s = 39978.29(\frac{340 + 8.32}{340} )\\\\f_s = 40,956.56 \ Hz[/tex]

[tex]f_s\approx 41 \ kHz[/tex]

Answer:

Answer to An object moves clockwise around a circle centered at the origin with radius 6 m beginning at ... 6 M Beginning At The Point (0,6) B. Find A Position Function R That Describes The Motion If It Occurs With Speed E T A. R(t)= S The Motion Of The Object Moves With A Constant Speed, Completing 1 Lap Every 12 S.

Explanation:

Answer:

B. carry a single circuit and are placed in individual cases.

Explanation:

An electric circuit can be defined as an interconnection of electrical components which creates a path for the flow of electric charge (electrons) due to a driving voltage.

Generally, an electric circuit consists of electrical components such as resistors, capacitors, battery, transistors, switches, inductors, etc.

Similarly, an integrated circuit (IC) also referred to as microchip can be defined as a semiconductor-based electronic component that comprises of many other tiny electronic components such as capacitors, resistors, transistors, and inductors.

Integrated circuits (ICs) are often used in virtually all modern electronic devices to carry out specific tasks or functions such as amplification, timer, oscillation, computer memory, microprocessor, etc.

A wafer can be defined as a thin slice of crystalline semiconductor such as silicon and germanium used typically for the construction of an integrated circuit.

In an integrated circuit, each wafer is cut into sections, which generally comprises of a single circuit that are placed in individual cases.

Additionally, a semiconductor can be defined as a crystalline solid substance that has its conductivity lying between that of a metal and an insulator, due to the effects of temperature or an addition of an impurity.

Answer: B got it right on the test just now

Explanation:

Answer:

sieving is when you separate particles of different sizes.

Explanation:

separating sand mixtures

separating chaffs from local garri

Answer:

2.00x 10 14th Hz

Explanation:

Answer:

2.99 x 10^14 Hz

Explanation:

E photon= hf (you have to solve for f)

f= E photon/h

f= 1.98 x 10^-19 J / 6.63 x 10^-34 J x s

f=2.99 x 10^14 Hz