The elements within a group tend to share
A. similar chemical properties and characteristics
B. similar atomic weights
c. similar atomic numbers
D. similar atomic symbols

THIS IS THE COMPLETE QUESTION BELOW

With what minimum speed must you toss a 130 g ball straight up to just touch the 14-m-high roof of the gymnasium if you release the ball 1.1 m above the ground

And what speed does the ball hit the ground? Solve this problem using energy.

Answer

a)minimum speed must you toss a 130 g is 15.9090m/s

b)speed the ball hit the ground is 16.57m/s

Explanation:

a)We know that For any closed/isolated system, the total energy is CONSERVED.

K.E. lost by the ball=The change in P.E of the ball at 1.1m above the ground as well as the P.E. of the ball at 14 m-high roof

This statement can be expressed as the expression below from K.E and P.E energy formula

P.E. = mgh

K.E. = (1/2)mv^2

Therefore,

(mgh1 - mgh2)=(1/2)mv^2

Where h2=the ball height above the ground=1.1m

h1=ball height at roof of the gymnasium= 14m

Then if we substitute we have

[(10) x (0.14) x (9.81)] - [(1.1) x (0.14) x (9.81)] = (1/2)(0.14)(v^2)

16.45137=0.065V^2

V=15.9090m/s

minimum speed must you toss a 130 g is 15.9090m/s

b)To calculate the speed the ball hit the ground?

This is the highest point (14m-high roof),and the type of the energy the ball possesses is Po.tential energy only.

At the lowest point (ground), the energy the ball possesses is K.E. only.

P.E at 10m-high roof = K.E. at ground.

(14) x (0.13) x (9.81) = (1/2) x (0.13) x v^2

17.8542= 0.065V^2

V= 16.57

Therefore,And speed the ball hit the ground is 16.57m/s

Answer:

The diameter is halved or reduced by a factor of 2

Explanation:

Because

f number = F/D

That is f number is inversely proportional to diameter so if it is doubled diameter is halved

Answer:

a) below the observed position

b) directly at the observed position

Explanation:

If I'm standing on the bank of a stream, and I wish to spear a fish swimming in the water out in front of me, I would aim below the observed fish to make a direct hit. This is because the phenomenon of refraction of light in water causes the light coming from the fish is refract away from the normal as it passes  into the air and into my eyes.

If I'm to zap the fish with a taser, I would aim directly at the observed fish because the laser (a form of concentrated light waves) will refract into the water, taking the same path the light from the fish took to get to my eyes.

Answer:

i) photons, they collide with the electrons

ii)when the energy of the photons is less than the work function there is no way to get out electrons

iii) he energy depends on the frequency in this Planck postulate

Explanation:

This exercise the photo cell is used for the photoelectric effect, this effect was explained by Einstein

i)  Where the light is supposed to act as a particular, therefore, it is called photons, they collide with the electrons and they can tear off the metal, with a collision it is very fast there is no measurable wait in the process.

ii) since we have a shock process, the equation must be fulfilled

          K = h f - Ф

where E = h f is the energy postulated by Plank and Ф the work function of the metal, therefore when the energy of the photons is less than the work function there is no way to get out electrons, which determines a threshold energy in the process

iii) From the same previous equation, the energy depends on the frequency in this Planck postulate, and not on the intensity squared as accepted in classical mechanics.

Answer:

The self-induced emf in this inductor is 4.68 mV.

Explanation:

The emf in the inductor is given by:

[tex] \epsilon = -L\frac{dI}{dt} [/tex]

Where:

dI/dt: is the decreasing current's rate change = -18.0 mA/s (the minus sign is because the current is decreasing)

L: is the inductance = 0.260 H

So, the emf is:

[tex] \epsilon = -L\frac{dI}{dt} = -0.260 H*(-18.0 \cdot 10^{-3} A/s) = 4.68 \cdot 10^{-3} V [/tex]

Therefore, the self-induced emf in this inductor is 4.68 mV.  

I hope it helps you!

The self-induced emf in this inductor is 4.68 mv.

Here

E = -LdI/dt

here

dI/dt represents the the decreasing current's rate change = -18.0 mA/s

the minus sign is due to the current is decreasing

L represents the inductance = 0.260 H

Now the emf should be

= -0260H * (-18.0.10^-3)

=  4.68 mv

hence, The self-induced emf in this inductor is 4.68 mv.

Learn more about current here: https://brainly.com/question/17080022

Answer:

The frequency of the coil is 7.07 Hz

Explanation:

Given;

number of turn of the coil, N = 200 turn

area of the coil, A = 300 cm² = 0.03 m²

magnitude of magnetic field, B = 30 mT = 0.03 T

maximum value of induced emf, E = 8 V

The maximum induced emf in the coil is given by;

E = NBAω

E = NBA(2πf)

[tex]f = \frac{E_{max}}{2\pi*NBA}[/tex]

where;

f is the frequency of the coil

[tex]f = \frac{E_{max}}{2\pi*NBA}\\\\f = \frac{8}{2\pi(200)(0.03)(0.03)} \\\\f = 7.07 \ Hz[/tex]

Therefore, the frequency of the coil is 7.07 Hz

Explanation:

Distance = speed × time

d = (11.6 km/h) (16 min × 1 hr / 60 min)

d = 3.09 km

Answer: distance = 3.09 km

Explanation: Distance = speed × time

distance = (11.6 km/h) (16 min × 1 hr / 60 min)

distance = 3.09 km

HOPE THIS HELPS YOU..

Distance = 27m

Displacement = 3 metres South

Distance is a scalar quantity and it represents the length of the path taken by a body.

Displacement is a vector quantity and it represents the distance between the start and end points of a body.

Now to the question:

The car drives 12 metres North i.e

North  (+ve)

∧

 |

 |  12m

 |

 |

The car then drives 15 metres South i.e

 |

 |

 |

 | 15m

 |

∨

South (-ve)

(a) The car's distance d, is just the total distance covered to drive North and then South. i.e

d = 12m + 15m = 27m

(b) The car's displacement D, however takes into respect, the direction of the car as it drives to and fro.

Let North be taken as positive direction

Let South be taken as negative direction.

This means that;

12 m North = +12 m

15 m South = -15m

Therefore;

D = +12 - 15

D = -3m

Since the displacement is negative, then it means that the direction of the total displacement is South.

Therefore, the displacement is 3 metres South

PS: The arrow diagram has also been attached to this response

Answer:

Ts = 3.0×10¯² sec

Explanation:

From the question given:

Ts = 2π √(4.5×10¯² Kg / 2.0×10³ Kg/s²)

The above expression can be evaluated as follow:

Pi (π) = 3.14

Ts = 2π √(4.5×10¯² / 2.0×10³)

Ts = 2 × 3.14 √(4.5×10¯² / 2.0×10³)

Ts = 6.28 × √(2.25×10¯⁵)

Ts = 6.28 × 4.74×10¯³

Ts = 3.0×10¯² sec

Answer:

350°C

Explanation:

Heat gained by water and aluminum = heat lost by iron

q₁ + q₂ = -q

m₁C₁ΔT₁ + m₂C₂ΔT₂ = -mCΔT

(1 kg) (900 J/kg/°C) (50°C − 21°C) + (2 kg) (4186 J/kg/°C) (50°C − 21°C) = -(2 kg) (449 J/kg/°C) (50°C − T)

(900 J/°C) (29°C) + 2 (4186 J/°C) (29°C) = -2 (449 J/°C) (50°C − T)

26,100 J + 242,788 J = -44,900 J + 898 (J/°C) T

898 (J/°C) T = 313,788 J

T = 350°C

Explanation:

Acceleration is change in velocity over change in time.

a = Δv / Δt

a = (0 m/s − 7.2 m/s) / (12 min ×  60 s/min)

a = -0.01 m/s²

Answer:

When we have a number in scientific notation like:

Ax10^n.

If n is positive, we need to add n zeros to the right of the value of A (before the decimal point)

Now, if n is negative, we need to add the decimal point n times to the left.

When we do not have any more digits in A to move the decimal point, we start to add zeros.

So for example, if we have:

7.42x10^-5

we move the decimal point 5 times to the left.

7.42x10^-5 = 0.742x10^-4 = 0.0742x10^-3 = 0.00742x10^-2

                  = 0.000742x10^-1 = 0.0000742.

So if we have n = -107

We move the decimal point to the left until we run out of digits in the number A, after that point, we start adding zeros in between the digits of A and the decimal point, until the number of times we moved the decimal point plus the number of zeros that we added is equal to 107.

Your bedroom has a rectangular shape, and you want to measure its area. You use a tape that is precise to 0.001 and find that the shortest wall in the room is 3.547 long. The tape, however, is too short to measure the length of the second wall, so you use a second tape, which is longer but only precise to 0.01 . You measure the second wall to be 4.79 long. Which of the following numbers is the most precise estimate that you can obtain from your measurements for the area of your bedroom?

b)If your bedroom has a circular shape, and its diameter measured 6.32 , which of the following numbers would be the most precise value for its area?

a)30 m^2

b) 31.4 m^2

c)31.37 m^2

d)31.371 m^2

Answer:

Part A

[tex]A = 16.99 \ m^2[/tex]

Part  B

 [tex]A_r =31.37 \ m^2[/tex]

Explanation:

From the question we are told that

   The  shortest wall is  [tex]x = 3.547 \ m[/tex]

      The  length of the second wall is [tex]y = 4.79 \ m[/tex]

Generally the area is mathematically evaluated as

           [tex]A = x * y[/tex]

=>    [tex]A = 3.547 * 4.79[/tex]

=>   [tex]A = 16.99 \ m^2[/tex]

Given that the diameter is  d =  6.32

Then the area is  

         [tex]A_r = \pi \frac{d^2}{4}[/tex]

         [tex]A_r =3.142 * \frac{6.32^2}{4}[/tex]

        [tex]A_r =31.37 \ m^2[/tex]

Answer: 112.5

Explanation:

divide the multiply

Answer:

C. Weight

Explanation:

A push or pull is a force.  The force caused by gravity is called weight.

Answer:

C: Weight

Explanation:

Answer:

Accuracy

Explanation:

I think accuracy is more important. When it comes to vital organs in the body, the exactness of getting the measurement is paramount. Accuracy deals with getting very close, almost exact you may say, to a known standard. Precision on the other hand, deals with how easy a measurement can be retaken, reproduced or remade, irrespective of how far or close they are from the accepted norm.

From this, we can agree that precision neglects the most important factor, closeness or say, exactness. Precision isn't bothered by it. And while that can be excused in a few instances, it certainly can not be permitted when it comes to life, or organs of the body

Answer:

The magnitude of the surface charge density on each plate is 6.714 x 10⁻⁸ C/m²

Explanation:

Given;

area of the parallel plates, A = 8 cm² = 8 x 10⁻⁴ m²

distance between the plates, d = 2.9 mm = 0.0029 m

potential difference applied to the plates, V = 22 V

The electric field between the plates is given by;

[tex]E = \frac{V}{d} \\\\E = \frac{22}{2.9*10^{-3}}\\\\E = 7586.207 \ V/m[/tex]

The surface charge density is given by;

σ = ε₀E

σ = (8.85 x 10⁻¹²)(7586.207)

σ = 6.714 x 10⁻⁸ C/m²

Therefore, the magnitude of the surface charge density on each plate is 6.714 x 10⁻⁸ C/m²

Answer:

5*10^8Nm

Explanation:

work done= displacement* force

Since the wind blows in the direction that the boats want to travel, all values would be positive.

10*10^3*(5*10^4)=5.00*10^8Nm

Answer:

5 x 10⁸ J

Explanation:

Recall that

Work Done = Force x Distance Traveled in the direction of the force

We are given :

Force = 5.00 x 10⁴ = 50,000 N

Distance Travelled in the direction of the force = 10.00 km = 10,000 m

Hence,

Work Done = 50,000 N x 10,000 m

= 500,000,000 J

= 5 x 10⁸ J

Answer

OPTION A is correct

a)increases by a factor of more than 2.

Explanation:

adiabatic process is a process that takes place without the transfer of heat or mass between a thermodynamic system and its surroundings.

It is a process in which no heat transfer takes place. It does not denote that the temperature is constant.

Then from an adiabatic system,

we know that

PV= constant

PV^γ= constant

γ=ratio of specific heat for the gas

Where P= pressure of the system

V= volume of the system

We can say P= 1/(V^γ)

Where γ >1

Which means the pressure is inversely proportional to the volume raise to power of gamma sign and whenever the pressure increases the volume decreases with V^γ.

The question says the volume is decreased by factor of two then V^γ will also decreased by factor of 2.

That means (2^γ) > 2

Since our γ > 1 Therefore, the pressure increases by a factor of more than 2.

Answer:

a) increases by a factor of more than 2.

Explanation:

In an adiabatic process,

[tex]PV^{Y} = constant[/tex]

we can say that the volume is inverse to the pressure as

[tex]V^{Y}[/tex]∝ [tex]\frac{1}{P}[/tex]

where

[tex]P[/tex] is the pressure

[tex]V[/tex] is the volume

[tex]Y[/tex] is the adiabatic index, and it is always greater than 1

If volume V is decreased by a factor of 2, then it is actually decreased by a factor of [tex]2^{Y}[/tex] in proportion to the pressure, and since [tex]Y[/tex] is always greater than 1, it is actually decreased by a factor greater than 2 in proportion to the pressure.

This means that the pressure will also increase by a factor greater than 2.

Explanation:

Distance is the length of the path.  Displacement is the difference between the final position and the initial position.

Speed = distance / time

= (50 m + 50 m + 50 m + 50 m) / (12.3 s + 12.5 s + 12.7 s + 12.6 s)

= (200 m) / (50.1 s)

= 3.99 m/s

Velocity = displacement / time

= (50 m − 50 m + 50 m − 50 m) / (12.3 s + 12.5 s + 12.7 s + 12.6 s)

= (0 m) / (50.1 s)

= 0 m/s

Answer:

a) 85.1 V

b)120.4 V

c) 10.24 A

d) 602.8 W

Explanation:

The reading of the ammeter is the root mean square value of current.

a) Vrms= Irms R

Irms= 7.24 A

R= 11.5 Ω

Vrms= 7.4A × 11.5Ω

Vrms= 85.1 V

b)

Peak value of voltage (Vo)= Vrms/0.707

Vo=85.1/0.707

Vo=120.4 V

c)

Peak current= Irms/0.707

Io= 7.24/0.707

Io= 10.24 A

d) average power= Irms^2 × R

Power= (7.24)^2 ×11.5

Power= 602.8 W

Explanation:

F = ma

F = m Δv / Δt

F = (70 kg) (8 m/s − 0 m/s) / 9 s

F ≈ 62 N

Answer:

a)13.33s

b)at highest point, the centripetal acceleration has its direction at downward path towards the center of the circular path, and the radius vector has its direction upward. Then acceleration=3.555m/s^2

c)c)at lowest point the centripetal acceleration has its direction upward towards the center of the circular path, and the radius vector has its direction downward Then acceleration=3.555m/s^2

Explanation

a)number of turns= 4.5

radius= 16m

We know that the period is the time taken by the wheel to complete one turn which can be calculated using below expresion

T= t/n

Where T= period of motion

t= Time taken by the wheel to finish n turns where our n= 4.5

T= (1×60)/4.5= 13.33s

Hence the period is 13.33s

Then the speed of the woman v= 2πr/T

v= (2×π×16)/13.33

v=7.5417m/s

b)at highest point, the centripetal acceleration has its direction at downward path towards the center of the circular path, and the radius vector has its direction upward.

a= v^2/r

Where r= radius

v= speed of the woman= 7.5417m/s

a=(7.5417m/s)^2/16

a=3.555m/s^2

The centripetal acceleration and radius vector are in opposite direction

c)at lowest point the centripetal acceleration has its direction upward towards the center of the circular path, and the radius vector has its direction downward

The magnitude of the acceleration is calculated below

a= v^2/r

Where r= radius

v= speed of the woman= 7.5417m/s

a=(7.5417m/s)^2/16

a=3.555m/s^2

Answer:

Rock cycle describes the concept in geology that shows the changes in the rock type in the geologic time.

Many processes undergoes in the rock cycle that leads to transition of rocks, the process that changes metamorphic rock to igneous rock is melting and crystallization. The metamorphic rock melts under high pressure and temperature and which crystallizes into a completely different kind of rock, called igneous rock.

Answer:

Melting followed by cooling

Wave Interference or Interference of wave

Answer:

  Ф_cube /Ф_sphere = 3 /π

Explanation:

The electrical flow is

      Ф = E A

where E is the electric field and A is the surface area

Let's shut down the electric field with Gauss's law

       Фi = ∫ E .dA = [tex]q_{int}[/tex] / ε₀

the Gaussian surface is a sphere so its area is

        A = 4 π r²

the charge inside is

        q_{int} = Q

we substitute

       E 4π r² = Q /ε₀

       E = 1 / 4πε₀   Q / r²

To calculate the flow on the two surfaces

* Sphere

       Ф = E A

        Ф = 1 / 4πε₀  Q / r² (4π r²)

        Ф_sphere = Q /ε₀

* Cube

Let's find the side value of the cube inscribed inside the sphere.

In this case the radius of the sphere is half the diagonal of the cube

          r = d / 2

We look for the diagonal with the Pythagorean theorem

         d² = L² + L² = 2 L²

         d = √2 L

we substitute

          r = √2 / 2 L

          r = L / √2

          L = √2  r

now we can calculate the area of ​​the cube that has 6 faces

          A = 6 L²

          A = 6 (√2  r)²

          A = 12 r²

the flow is

          Ф = E A

          Ф = 1 / 4πε₀  Q/r²  (12r²)

          Ф_cubo = 3 /πε₀  Q

the relationship of these two flows is

         Ф_cube /Ф_sphere = 3 /π

Answer:

A) 7.37 x 10^-4 N

B) The resultant force will be towards the -x axis

Explanation:

The three masses have mass = 3500 kg

For the force of attraction between the mass at the origin and the mass -100 cm away:

distance r = 100 cm = 1 m

gravitational constant G= 6.67×10^−11 N⋅m^2/kg^2

Gravitational force of attraction [tex]F_{g}[/tex] = [tex]\frac{Gm^{2} }{r^{2} }[/tex]

where G is the gravitational constant

m is the mass of each of the masses

r is the distance apart = 1 m

substituting, we have

[tex]F_{g}[/tex] = [tex]\frac{6.67*10^{-11}*3500^{2} }{1^{2} }[/tex] = 8.17 x 10^-4 N

For the force of attraction between the mass at the origin and the mass 320 cm away

distance r = 320 cm = 3.2 m

[tex]F_{g}[/tex] = [tex]\frac{Gm^{2} }{r^{2} }[/tex]

substituting, we have

[tex]F_{g}[/tex] = [tex]\frac{6.67*10^{-11}*3500^{2} }{3.2^{2} }[/tex] = 7.98 x 10^-5 N

Resultant force = (8.17 x 10^-4 N) - (7.98 x 10^-5 N) = 7.37 x 10^-4 N

B) The resultant force will be towards the -x axis