Andy took a bus and then walked from his home to downtown.
For the first 1.6 hour, the bus drove at an average speed of 15
km/h. For the next 0.4 hours, he walked at an average speed
of 4.5 km/h. What was the average speed for the whole
journey?

Answer:

d) electrons removed.

Explanation:

Two insulators are electrically neutral, that is, the number of electrons and protons are equal. When one insulator is rubbed against another, electrons are removed from one of the insulators due their high mobility. The insulator which lost the electrons becomes positively charged while the one that gained the electron becomes negatively charged.

Therefore, when rubbing two insulators together, the one that gets a positive charge has had electrons removed.

Answer:

sunspots looking dark

Answer: you would feel more gravity

Explanation: the more mass of an object the more pull

Answer:

it A

Explanation:

Its a negative ion that hss one less valence electron than a netural bromine atom

Explanation:

imagine a column of water of 1 m² that starts at the surface of the ocean, which goes straight down 700m.

You need to calculate the pressure induced by only the column of water.

Please understand that the total pressure is found by adding the pressure of the column of water AND that of the pressure of the atmosphere.

p = F/A

p = pressure in Pa

F = Force in N

A = area in m²

To calculate the Force that gravity has on that column of water, you simply use:

F = m * g

where g = 9.81 kgm/s²

So first you need to calculate the mass of the column sea water with a density of 1.024*10³ kg/m³

Answer:

9.2 s

Explanation:

Given:

v₀ = 46 m/s

v = 0 m/s

a = -5 m/s²

Find: t

v = at + v₀

0 m/s = (-5 m/s²) t + 46 m/s

t = 9.2 s

Answer:

Explanation:

According to Johannes Kepler, the laws governing planetary motion

states that:

1. The orbit of a planet is an ellipse with the Sun at one of the two foci.

2. A line segment joining a planet and the Sun sweeps out equal areas          

   during equal intervals of time.

3. The square of a planet's orbital period is proportional to the cube of the semi-major of its orbit.

Johannes Kepler was a German astronomer, mathematician, and astrologer

Born: 27 December 1571, Weil der Stadt, Germany

Died: 15 November 1630

Explanation:

Some standard unit conversion are 1 mile = 1.609344 km, 1 ft.= 30.48 cm,

1 km= 1000 m or 1 m = 0.001 km and 1 m= 100 cm or 1 cm=0.01 m.

Now, use these values to convert the given lengths.

A. length of cave = 5 miles (given)

From standard value 1 mile = 1.609344 km

[tex]\Rightarrow[/tex] 5 miles = [tex]\times[/tex] 1.609344 km= 8.04672 km,

[tex]\Rightarrow[/tex] 5 miles =8.04672 [tex]\times[/tex] 1000 m= 8046.72 m [ as 1 km = 1000 m]

[tex]\Rightarrow[/tex] 5 miles = 8046.72 [tex]\times[/tex] 100 cm=804672 cm

B. Height of the waterfall = 1235 ft. (given)

1 ft.= 30.48 cm [ from standard value]

[tex]\Rightarrow[/tex] 1235.2 ft.= 1235.2[tex]\times[/tex] 30.48 cm=37648.896 cm,

[tex]\Rightarrow[/tex] 1235.2 ft.=37648.896 [tex]\times[/tex] 0.01 m =376.48896 m [ as 1 cm = 0.01 m]

[tex]\Rightarrow[/tex] 1235.2 ft.=376.48896 [tex]\times[/tex] 0.001 km =0.37648896 km [ as 1 m = 0.001 km]

C. Height of the mountain= 21320 ft. (given)

From standard value: 1 ft.= 30.48 cm

[tex]\Rightarrow[/tex] 21320 ft.= 21320 [tex]\times[/tex] 30.48 cm=649833.6 cm,

[tex]\Rightarrow[/tex] 21320 ft.=649833.6 [tex]\times[/tex] 0.01 m =6498.336 m [ as 1 cm = 0.01 m]

[tex]\Rightarrow[/tex] 21320 ft.=6498.336 [tex]\times[/tex] 0.001 km =6.498336 km [ as 1 m = 0.001 km].

D. Depth of canyon =6630 ft.

From standard value: 1 ft.= 30.48 cm

[tex]\Rightarrow[/tex] 6630 ft.= 6630 [tex]\times[/tex] 30.48 cm=202082.4 cm,

[tex]\Rightarrow[/tex] 6630 ft.=202082.4  [tex]\times[/tex] 0.01 m =2020.824  m [ as 1 cm = 0.01 m]

[tex]\Rightarrow[/tex] 6630 ft.=2020.824  [tex]\times[/tex] 0.001 km =2.020824  km [ as 1 m = 0.001 km].

Density = (mass) / (volume)  (definition)

(Density) x (volume)  =  (mass)

(volume)  =  (mass) / (density)

Volume = (57.3 g) / (1.38 g/mL)

Volume = 41.5 mL

Answer:

41.5

Explanation:

Got answer correct on EDG

Responder:

20πrads ^ -1; 24πrads ^ -1; 0,1 seg; 10 Hz

Explicación:

Dado lo siguiente:

Radio (r) del círculo = 120 cm

600 revoluciones por minuto en radianes por segundo

(600 / min) * (2π rad / 1 rev) * (1min / 60seg)

(1200πrad / 60sec) = 20π rad ^ -1

Velocidad angular (w) = 20πrads ^ -1

Velocidad lineal = radio (r) * velocidad angular (w)

Velocidad lineal = (120/100) * 20πrad

Velocidad lineal = 1.2 * 20πrads ^ -1 = 24πrads ^ -1

C.) Período (T):

T = 2π / w = 2π / 20π = 0.1 seg

D.) Frecuencia (f):

f = 1 / T = 1 / 0.1

1 / 0,1 = 10 Hz

The magnitude of total displacement of  Barney  is 16.12 meters in an angle 29.75 ° with north in north east direction..

The term "displacement" refers to a shift in an object's position. It is a vector quantity with a magnitude and direction. The symbol for it is an arrow pointing from the initial location to the ending place.

Given parameters:

Barney walks 6 steps north, 4 steps to the west, 2 more steps north, and 10 more steps to the west.

He walks = ( 6+2)steps towards north.

= 8 steps towards north.

He walks = ( 4 + 10 ) steps to the west

= 14 steps to the west.

The magnitude of his total displacement = √(8² + 14²) meters = 16.12 meters.

And the direction is = tan⁻¹(8/14) north east. = 29.75 ° with north in north east direction.

Hence, the magnitude of total displacement of  Barney  is 16.12 meters  in an angle 29.75 ° with north in north east direction..

Learn more about displacement here:

https://brainly.com/question/11934397

#SPJ2

Answer:

A) 0.9844 s

B) x2 = 0.4587 m

C) v = 6.657 m/s

Explanation:

We are given;

Height of take off point above pool; x1 = 1.8 m

Initial take off velocity; u = 3 m/s

Final velocity at highest point before free fall; v = 0 m/s

B) To find the highest point above the board her feet reaches means the distance from take off to the top of the motion just before free fall.

Thus, we will be using equation of motion and we have;

v² = u² + 2gs

Now, let s = x2 which will be the distance between take off and the top before free fall.

So;

v² = u² + 2g(x2)

Now,since the motion is against gravity, g will be negative.

Thus;

v² = u² + 2(-9.81)(x2)

Plugging in the relevant values to give;

0² = 3² - (19.62x2)

19.62(x2) = 9

x2 = 9/19.62

x2 = 0.4587 m

A) We want to find how long her feet is in air.. It means we want to find out the time to get to a distance of x1 and also the time to achieve the distance (x1 + x2) on free-fall.

Thus, using equation of motion;

v = u + gt

Again, g = -9.81

Thus;

0 = 3 - 9.81t1

9.81t1 = 3

t1 = 3/9.81

t1 = 0.3058 s

Now, for the time taken to achieve the distance (x1 + x2) on free-fall, we will use the formula;

s = ut + ½gt²

Where s = (x1 + x2) = 1.8 + 0.4587 = 2.2587 m

And now, u = 0 m/s because the start of the free fall is from maximum height with velocity of 0 m/s. Again, g = - 9.81 m/s²

Thus;

2.2587 = 0 - ½(-9.81)(t2)²

2.2587 = 4.905(t2)²

(t2)² = 2.2587/4.905

(t2)² = 0.4605

t2 = √0.4605

t2 = 0.6786 s

Thus, total time of feet in air = t1 + t2 = 0.3058 + 0.6786 = 0.9844 s

C) Velocity when feet hit the water would be given by;

v = u + gt

Where u = 0 m/s and t = t2 = 0.6786

Since it's in direction of gravity, g = 9.81 m/s

v = 0 + (0.6786 × 9.81)

v = 6.657 m/s

Answer:

87 km/h

Explanation:

Answer:

3.68×10¯⁶ m

Explanation:

The following data were obtained from the question:

Mass (m) = 5 g

Tension (T) = 180 N

Frequency (f) = 260 Hz

Wavelength (λ) = 0.60 m.

Length (L) =?

Next, we shall determine the period of the wave. This can be obtained as follow:

Period is simply defined as the time taken to complete 1 oscillation. Mathematically, it is represented as:

Period (T) = 1/frequency (f)

T = 1/f

Thus, with the above formula, the period of the wave can be obtained as shown below:

Frequency (f) = 260 Hz

Period (T) =?

T = 1/f

T = 1/260

T = 3.85×10¯³ s

Finally, we shall determine the length of the string as follow:

Period (T) = 3.85×10¯³ s

Acceleration due to gravity (g) = 9.8 m/s²

Pi (π) = 3.14

Length (L) =?

T = 2π√(L/g)

3.85×10¯³ = 2 × 3.14 × √(L/9.8)

3.85×10¯³ = 6.28 × √(L/9.8)

Divide both side by 6.28

3.85×10¯³ / 6.28 = √(L/9.8)

Take the square of both side

(3.85×10¯³ / 6.28)² = L/9.8

Cross multiply

L = (3.85×10¯³ / 6.28)² × 9.8

L = 3.68×10¯⁶ m

Therefore, the length of the string is 3.68×10¯⁶ m

Answer:

25104 J

Explanation:

We are given;

Mass; m = 600 g

Change in temperature;Δt = (40 - 30) = 10°C

Specific heat of water; c = 4.184 J/g°C

Now, to find how many joules, we simply use the formula for quantity of heat.

Thus;

Q = mcΔt

Plugging in the relevant values to give;

Q = 600 × 4.184 × 10

Q = 25104 J

Quantity of heat = 25104 J

Answer:

tasteless

Explanation:

Answer:

57.42 N

Explanation:

We first find the acceleration knowing that it goes from rest to 8.3 m/s in 0.13 seconds,

Therefore, the acceleration is:

[tex]a=\frac{v_f-v_i}{time} =\frac{8.3-0}{0.13 } =63.8\,\,m/s^2[/tex]

Now we use this to calculate the average net force by multiplying mass times acceleration:

F = m * a = 0.9 (63.8) = 57.42 N

Answer:

c)Average acceleration is always equal to the change in velocity of an object divided by the time interval.

Explanation:

Because average acceleration= a2+a1/2

Which is equal to change in velocity which is a time rate of change of velocity v-u/t which actually explains average acceleration

That statement is false.

Proteins are.

Answer:

That statement is false.

Proteins are.

Explanation:

Answer:

The answer is transferred. So your answer will be: When you do work on an object some of the energy is transferred to that object.

Answer:

7 × 60 (minute to seconds) = 420 seconds

1.38 × 420 = 579.6m

Answer:

The value is   [tex]q =  5.72 *10^7 \  C[/tex]

Explanation:

From the question we are told that

  the mass is  [tex]m  =  1.53 \ kg[/tex]

      The  atomic mass is  [tex]u  =  244 g/mol =  0.244 kg/mol[/tex]

      The number of protons on each atom is [tex]N  =  94 \  protons[/tex]

       The mass of one atomic mass unit is [tex]M  = 1.66 *10^{-27} \  kg[/tex]

Generally the number of atoms present is  

       [tex]k  =  \frac{m *  N_a }{u}[/tex]

Here  [tex]N_a[/tex] is the Avogadro constant  with value [tex]N_a  =  6.023  *10^{23} \  atoms /mol[/tex]

=>    [tex]k  =  \frac{1.53 * 6.023*10^{23}}{ 0.244}[/tex]

=>   [tex]k  =  3.8 *10^{24} \  atoms[/tex]

The coulombs of positive charge on the plutonium is mathematically represented as

     [tex]q =  k *  N  *  e[/tex]

Here e is the charge on a proton with value [tex]e =  1.60 *10^{-19}\  C[/tex]

    [tex]q = 3.8 *10^{24} *  94 *  1.60*10^{-19}[/tex]

           [tex]q =  5.72 *10^7 \  C[/tex]

Answer:

A closest

Explanation:

This is because the electric field will be strongest or largestwhen the equipotential curves are closest together

We know that the field is

E= V/d

Where is distance and we see that d being the denominator will only make E bigger if it becomes smaller that is the curves closest

Answer:

Bolt

Explanation:

Answer:

The time taken is   [tex]t = 0.4103 \ s[/tex]

Explanation:

From the question we are told that

  The  speed is  [tex]v  =  130 \  mi/h =  58 \  m/s[/tex]

   The  length of the tennis court [tex]l =  78 \ ft = \frac{78}{3.281}= 23.8 \ m[/tex]

 Generally the time taken is mathematically represented as

      [tex]t =  \frac{ 23.8}{ 58}[/tex]

=>        [tex]t = 0.4103 \ s[/tex]

Answer:

The time taken to drive on this high way is 6.48 hours

Explanation:

Given;

average velocity, v = 24 m/s

distance of travel, d = 560 km = 560,000 m

The distance traveled is given by;

[tex]d = (\frac{v+u}{2} )t\\\\d =( 24 \ m/s)t\\\\t = \frac{d}{24} \\\\t = \frac{560,000}{24}\\\\t = 2333.33 \ s = 6.48 \ hrs[/tex]

Therefore, the time taken to drive on this high way is 6.48 hours

Answer:

x = 78.9 cm

Explanation:

The instantaneous velocity v of the marble as it slides past the putty, as a function of time t, is given by

[tex]v(t)=u-bt+ct^3[/tex]

u = 2.50 m/s, b = 3.55 m/s², and c = 6.70 m/s⁴

As the marble exits the region covered in putty, the marble\'s instantaneous acceleration goes to zero.

[tex]a=\dfrac{dv}{dt}\\\\a=\dfrac{d(u-bt+ct^3)}{dt}\\\\a=-b+3ct^2[/tex]

or

[tex]0-3.55+3\times 6.7t^2\\\\0=-3.55+20.1t^2\\\\t=\sqrt{\dfrac{3.55}{20.1}} \\\\t=0.42\ s[/tex]

Let x is the length of the track.

[tex]v=\dfrac{dx}{dt}\\\\\text{or}\\\\\int\limits_0^x {dx} =\int\limits^{4.2}_0 {vdt} \\\\x=\int\limits^{4.2}_0 {u-bt+ct^3} \, dt\\\\x=[ut-\dfrac{bt^2}{2}+\dfrac{ct^4}{4}]_0^ {0.42}\\\\\text{Putting limits}\\\\x=0.42u-\dfrac{b(0.42)^2}{2}+\dfrac{c(0.42)^4}{4}\\\\\text{Now, put values of u,b and c}\\\\x=0.42(2.5)-\dfrac{3.55\times (0.42)^2}{2}+\dfrac{6.7\times (0.42)^4}{4}\\\\x=0.789\ m\\\\x=78.9\ cm[/tex]

So, the length of the track that is covered with putty is 78.9 cm.

The length of the track is covered with putty is 0.789 m.

The instantaneous velocity v of the marble as a function of time t is given below.

[tex]v(t)=u-bt+ct^3[/tex]

Where t = 0 at the moment when the marble first comes into contact with the putty. Also given that, u = 2.50 m/s, b = 3.55 m/s², and c = 6.70 m/s⁴.

Given that the acceleration = 0 as the marble exits the region covered in putty. The acceleration is the rate change in the velocity with respect to time.

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

[tex]a = \dfrac {d(u-bt+ct^3)}{dt}[/tex]

[tex]a = -b + 3ct^2[/tex]

Substituting the values in the above equation, we get the time.

[tex]0 = -3.55 + 3 \times 6.70 t^2[/tex]

[tex]t^2 = 0.1766[/tex]

[tex]t = 0.42 \;\rm s[/tex]

Hence the time interval is t =0 to t = 0.42 seconds.

Let us consider that the length of the track is l. Then the velocity can be written as the function of length is given below.

[tex]v = \dfrac {dl}{dt}[/tex]

[tex]dl = vdt[/tex]

[tex]\int_{0}^{t}dl = \int_{0}^{0.42} vdt[/tex]

[tex]l = \int_{0}^{0.42} (u-bt+ct^3) dt[/tex]

[tex]l =[ ut-\dfrac {bt^2}{2} + \dfrac {ct^4}{4} ]_0^{0.42}[/tex]

Putting the value t = 0.42,

[tex]l = 2.50 \times 0.42 - \dfrac {3.55 \times (0.42)^2}{2} + \dfrac { 6.70 \times (0.42)^4}{4}[/tex]

[tex]l = 0.789 \;\rm m[/tex]

Hence the length of the track is covered with putty is 0.789 m.

To know more about velocity and acceleration, follow the link given below.

https://brainly.com/question/2437624.

Answer:

The ratio of the model size is 1 : 2000

Explanation:

Given

Real Diameter =  0.012 um

Scale Diameter =  24 um

Required

Determine the scale ratio

The scale ratio is calculated as follows;

[tex]Scale = \frac{Real\ Measurement}{Scale\ Measurement}[/tex]

Substitute values for real and scale measurements

[tex]Scale = \frac{0.012\ um}{24\ um}[/tex]

Divide the numerator and the denominator by 0012um

[tex]Scale = \frac{1}{2000}[/tex]

Represent as ratio

[tex]Scale = 1 : 2000[/tex]

Hence, the ratio of the model size is 1 : 2000

Answer:

Explanation: The Answer Is D Two Thousand & The Number



Answer:

The value is [tex]v  =  2.999 *10^{8} \  m/s[/tex]

Explanation:

From the question we are told that

   The time taken to travel to the planet from earth is [tex]t = 189 \ light-years[/tex]

    The  time to be spent on the ship is  [tex]t_{s} =  12 \  years[/tex]

Generally speed can be obtained using the mathematical relation represented below

       [tex]t_s  =  2 * t *  \sqrt{1 -  \frac{v^2}{c^2 } }[/tex]

The 2 in the equation show that the trip is a round trip i.e going and coming back

=>    [tex]12 =  2 * 189 *  \sqrt{1 -  \frac{v^2}{(3.0*10^{8})^2 } }[/tex]

=>     [tex]v  =  2.999 *10^{8} \  m/s[/tex]