A sailboat took 25 hours to cover 1/4 of a journey. Then, it
covered the remaining 144 miles in 3.5 hours. What was the
average speed for the whole journey?
mph

Answer: Option (1) 70 kJ

Explanation:

Given that;

melting point of the substance T₁ is 20°C , Boiling point of the substance T₂ is 150°C , heat of fusion L₁ is 3.5 x 10⁴ J/kg , heat of vaporization L₂ is 7 x 10⁴ J/kg , Specific heat in solid state C₁ is 600 J/kg.K , Specific heat in liquid state C₂ is 1000 J/kg.K, Specific heat in gaseous state C₃ is 400 J/(kg.K) , Mass of the substance m is 0.5 kg , Initial temperature of the substance T₃ is 170°C , Final temperature of the substance  T₄ is 88°C .

Now  Heat given up by the substance to reach boiling point 150°C is

Q₁ = mC₃(T₃ - T₂)

Q₁ = (0.5)(400)(170 - 150)

Q₁ = 4000 J

Heat given up by the substance to turn into liquid from gaseous state at 150°C

Q₂ = mL₂

Q₂ = (0.5)(7x10⁴)

Q₂ = 35000 J

Heat given up by the substance to reach 88°C in liquid state from 150°C

Q₃ = mC₂(T₂ - T₄)

Q₃ = (0.5)(1000)(150 - 88)

Q₃ = 31000 J

Total heat given up by the substance

Q = Q₁ + Q₂ + Q₃

Q = 4000 + 35000 + 31000

Q = 70000 J

Q = 70 kJ

Therefore The quantity of heat given up by 0.50 kg of the substance when it is cooled from 170◦C to 88◦C, at a pressure of 1.0 atmosphere, is closest to 70 kJ

Answer:To protect the human body from foreign bodies from the outside environment.

Explanation:

Answer:

The acceleration of the particle is 2 m/s²

The position of the particle is 9m

Explanation:

Given;

particles velocity, v = 2t m/s

The acceleration of the particle is given by;

a = dv/dt

a = d(2t) /dt

a = 2 m/s²

The acceleration of the particle is 2 m/s²

The position of the particle is given by;

s = ut + ¹/₂at²

Since the particle was released from rest, u = 0

s = 0(3) + ¹/₂(2)(3)²

s = 0 + 9 m

The position of the particle when t = 3 s is 9m

Answer:

I believe the answer is 10.82 m/s.

Explanation:

I just saw that the question asked for the TOTAL DISTANCE.. which means to add. And I added 4.83 and 5.99 together which then lead me to get 10.82 m/s. So yeah i think that's the answer. Hope this helps.

Answer:

a) 4652 cal

b) 8000 cal

Explanation:

Amount of heat transferred

Q1 = mL(v)

Q1 = 8.63 * 539

Q1 = 4652 cal

Amount of heat transferred to the water

Q2 = mcΔT

Q2 = 100 * 1 * (100 - 20)

Q2 = 8000 cal

Q = Q1 + Q2

Q = 4652 + 8000

Q = 12652 cal

b)

Heat transferred to the copper bowl

Q(b) = m(b) * c(b) * ΔT

Q(b) = 0.13 * 0.0923 * (100 - 20)

Q(b) = 0.96 cal

c)

Original heat of the cylinder

Q(c) = Q + Q(b)

m(c) * c(c) * ΔT = Q + Q(b), making ΔT subject of the formula

ΔT = (Q + Q(b))/ (m(c) * c(c))

ΔT = (12652 + 0.96) / (0.42 * 1)

ΔT = 12652.96/0.42

ΔT = 30126.1

Answer:

Vf = 69.56 cm/s

Explanation:

In order to find the final speed of the ramp, we will use the equations of motion. First we use second equation of motion to find out the acceleration of marble:

s = Vi t + (1/2)at²

where,

s = distance traveled = 160 cm

Vi = Initial Speed = 0 cm/s (since, marble starts from rest)

t = time interval = 4.6 s

a = acceleration = ?

Therefore,

160 cm = (0 cm/s)(4.6 s) + (1/2)(a)(4.6 s)²

a = (320 cm)/(4.6 s)²

a = 15.12 cm/s²

Now, we use first equation of motion:

Vf = Vi + at

Vf = 0 cm/s + (15.12 cm/s²)(4.6 s)

Vf = 69.56 cm/s

Answer:

a) to the right

b) up

c) down

d) there will be no force on the proton

e) there will be no force on the proton

Explanation:

The complete question is

If the velocity of a proton is straight up(thumb pointing up) then RHR2 (right hand rule) shows that the force points to the left. What would the direction of the force be if the velocity were a)down, b)to the right, c)to the left, d)into the page, and e)out of the page?

The right hand rule for a positive charge states that...

Hold the thumb of the right hand at right angle to the rest of the fingers, and the rest of the fingers parallel to one another, and pointing away from the body. If the thumb shows the velocity of a positive charge in a magnetic field, and the fingers all point in the direction of the magnetic field, then the palm will push in the direction of the force on the positive charge (proton).

From this, we can deduce from the original statement about this proton that the direction of the field is into the screen of this computer. with that field direction held constant, we can work out that

a) if the thumb point down, the force will be to the right

b) if the thumb points to the right, the force will be upwards

c)  if the thumb points to the left, the force is downwards

d)  if the thumb points into the page, then there will be no force on the proton since the proton must travel perpendicularly to the magnetic field for a force to be induced on it

e) explanation is the same as foe option d.

Answer:

[tex]s=6.86m/s^2[/tex]

Explanation:

Hello,

In this case, considering that the acceleration is computed as follows:

[tex]a=\frac{v_{final}-v_{initial}}{t}[/tex]

Whereas the final velocity is 28.82 m/s, the initial one is 0 m/s and the time is 4.2 s. Thus, the acceleration turns out:

[tex]a=\frac{28.82m/s-0m/s}{4.2s}\\ \\s=6.86m/s^2[/tex]

Regards.

Answer:

2.68 hours

Explanation:

A.) Suppose the wind blows out from the west (with the air moving east). The pilot should then head her plane to northwest direction to move directly north.

B.) Given that plane flies at a speed of 102 km/h in still air. And the wind blows out from the west (with the air moving east) at a speed of 46 km/h.

The plan resultant speed can be calculated by using pythagorean theorem.

Resultant Speed = Sqrt( 102^2 + 46^2 )

Resultant Speed = Sqrt( 12520)

Resultant speed = 111.89 km/h

From the definition of speed,

Speed = distance/time

Where distance = 300 km

Substitute the resultant speed and the distance into the formula.

111.89 = 300/time

Time = 300/111.89

Time = 2.68 hours

Therefore, it take her 2.68 hours to reach a point 300 km directly north of her srarting point

Answer:

False

Explanation:

Becuase the average amu of 40 is represented

Answer:

Time taken by car to cover 10m is 5.42 seconds and final velocity is 0m/s.

Answer:

B. Running one mile faster than normal

Explanation:

Just took the quiz, good luck ❤

The best example of increasing the intensity of a workout is running one file faster than normal. Hence, option B is correct.

Exercise is a physical activity for the body that improves or preserves physical fitness as well as general health and wellness.

It is done for a variety of objectives, such as support growth and enhance strength, needs to better and also the cardiovascular system, refine sports skills, maintain or lose weight, improve health, or just for fun. Many people like to work outside where they may interact, gather in groups, and enhance their physical and emotional well-being.

The amount of advised exercise for health benefits varies on the objective, the style of activity, and the age of the individual. Exercise is better for you than not at all, even if it is only a little.

Therefore, the best example of increasing the intensity of workout or exercise by running one mile faster than normal.

To know more about Exercise:

https://brainly.com/question/13128077

#SPJ6

Answer:

330 km

55*6= 330 km. An easy formula for this is multiplying time with speed.

Explanation:

330 kilometros

55 * 6 = 330 km. Una fórmula fácil para esto es multiplicar el tiempo por la velocidad.

Answer:330 km

Explanation:55*6= 330 km. An easy formula for this is multiplying time with speed.

Hey There!! ~

The answer to this is: Complete these sentences.

If a bouncing ball has a total energy of 20 J and a kinetic energy of 5 J, the ball’s potential energy is 15J.

If the kinetic energy of the ball decreases, then the potential energy will Increase.

Hope It Helped!~

[tex]ItsNobody[/tex]~

Answer:Compared to other pathogens, such as bacteria, viruses are minuscule. And because they have none of the hallmarks of living things — a metabolism or the ability to reproduce on their own, for example — they are harder to target with drugs.

Explanation:

Answer:

Explanation:

From the question we are told that

  The  height is  [tex]h  =  0.518 \  m[/tex]

    The  sphere density is  [tex]\rho =  22.2g/cm^3 =  \frac{22.2 }{1000}  *  1*10^{6} =  22200 kg/m^3[/tex]

    The  radius is  [tex]r =  2.12 \  mm =0.00212 \ m[/tex]

Generally the power required  is mathematically represented as

   [tex]P  =  \frac{16 *  \pi *  \rho *  r *  g *  h^2 * c }{3}[/tex]

substituting values  

    [tex]P  =  \frac{16 * 3.142 *  22200 *  0.00212 *  9.8 *  0.518^2 *  3.0*10^{8}}{ 3}[/tex]

   [tex]P  = 6.22*10^{11} \  W[/tex]

Answer:

7.5 meters

Explanation:

Answer:

7.5 kilometers

Explanation:

The distance can be found by multiplying the speed by the time.

[tex]d=s*t[/tex]

The car's speed is 1.5 kilometers per minute. It is traveling for 5.0, or 5  minutes. Therefore,

[tex]s= 1.5 km/min\\t=5 min[/tex]

Substitute the values into the formula.

[tex]d=1.5 km/min * 5 min[/tex]

Multiply. When you multiply, the minutes, or "min" will cancel each other out.

[tex]d= 1.5 km * 5[/tex]

[tex]d=7.5 km[/tex]

The distance the car travels is 7.5 kilometers.

Answer:

first law is your answer, if I'm not wrong

Answer:

i think it's the first law of motion :)

Explanation:

Answer:

Hewo Otaku Kun Here! (UwU)

Explanation:

1. A rock sitting at the edge of a cliff has potential energy. If the rock falls, the potential energy will be converted to kinetic energy.

2. Tree branches high up in a tree have potential energy because they can fall to the ground.

3. A stick of dynamite has chemical potential energy that would be released when the activation energy from the fuse comes into contact with the chemicals.

4. The food we eat has chemical potential energy because as our body digests it, it provides us with energy for basic metabolism.

5. A stretched spring in a pinball machine has elastic potential energy and can move the steel ball when released.

6. When a crane swings a wrecking ball up to a certain height, it gains more potential energy and has the ability to crash through buildings.

7. A set of double "A" batteries in a remote control car possess chemical potential energy which can supply electricity to run the car.

happy to help!

from: Otaku Kun ^^

Given :

A kayak on a lake is moving at a constant speed of 4.1 m/s in a direction 41.6° north of west.

To Find :

After 10 min :

(a) how far west the kayak has traveled km.

(b) how far north the kayak has traveled km.

Solution :

a) Time taken in seconds :

[tex]t=10\times 60 \ s = 600\ s[/tex] .

Distance travelled in 600 s is :

[tex]D=s\times t\\\\D=4.1\times 600\ m\\\\D=2460\ m[/tex]

Distance in km is :

[tex]D=\dfrac{2460}{1000}=2.46\ km[/tex]

b) Now , distance from the north is given by :

[tex]d=D\times sin\ 41.6^o\\\\d=2.46 \times sin\ 41.6^o\\\\d=1.63\ km[/tex]

Hence , this is the required solution .

Answer:

h = 1.07 m

Explanation:

It is given that,

The average sped of the kingfisher, v = 4.6 m/s

Time, t = 1.4 s

Final speed, v = 0 (as it hits the water)

We need to find the height from which the bird dove. Let the height is h. According to the conservation of energy.

[tex]mgh=\dfrac{1}{2}mv^2\\\\h=\dfrac{v^2}{2g}\\\\h=\dfrac{(4.6)^2}{2\times 9.8}\\\\h=1.07\ m[/tex]

So, the bird dove from a height of 1.07 m.

Answer:

a. 1.80 %

b. 0.60 %

c. 1.20 %

d. 0.60 %

e. 0.60 %

Explanation:

In order to calculate percent uncertainties in each case, we forst need to calculate the average value:

Average Diameter = (16.4 mm + 16.8 mm + 16.9 mm + 16.6 mm +16.8 mm)/5

Average Diameter = 16.7 mm

Now, the formula for percent uncertainty is:

% Uncertainty = (Uncertainty/Average) * 100 %

where,

Uncertainty = |Value - Average|

For Each Case:

a. 16.4 mm:

Uncertainty = |16.4 mm - 16.7 mm| = 0.3 mm

Therefore,

% Uncertainty = (0.3 mm/16.7 mm) * 100%

% Uncertainty = 1.80 %

b. 16.8 mm:

Uncertainty = |16.8 mm - 16.7 mm| = 0.1 mm

Therefore,

% Uncertainty = (0.1 mm/16.7 mm) * 100%

% Uncertainty = 0.60 %

c. 16.4 mm:

Uncertainty = |16.9 mm - 16.7 mm| = 0.2 mm

Therefore,

% Uncertainty = (0.2 mm/16.7 mm) * 100%

% Uncertainty = 1.20 %

d. 16.6 mm:

Uncertainty = |16.6 mm - 16.7 mm| = 0.1 mm

Therefore,

% Uncertainty = (0.1 mm/16.7 mm) * 100%

% Uncertainty = 0.60 %

e. 16.8 mm:

Uncertainty = |16.8 mm - 16.7 mm| = 0.3 mm

Therefore,

% Uncertainty = (0.1 mm/16.7 mm) * 100%

% Uncertainty = 0.60 %

Answer:

C. 30.6m

Explanation:

To find the height of the tower, we are to use Newtons law of motion to solve this problem. Since the penny is falling from the top of the tower, it is acted by the acceleration due to gravity. The formula to be used is:

[tex]H=ut+\frac{1}{2}gt^2[/tex]

Where H is the height of the tower, t is the time taken to hit the ground, u is the initial velocity and g is the acceleration due to gravity.

Given that, t = 2.5 s, g =9.8 m/s², u = 0 m/s (at the top of tower)

[tex]H=ut+\frac{1}{2}gt^2\\\\H=0(2.5)+ \frac{1}{2}(9.8)(2.5)^2\\\\H=30.6\ m[/tex]

Answer:

a

 The  charge is  [tex]Q =  2.0*10^8 \  C[/tex]

b

The number of electrons  [tex]N  =  1.25 *10^{27} \  electrons[/tex]

Explanation:

From the question we are told that

    The  maximum rate of charge flow is  [tex]\frac{dq}{dt} = I =  20000 \  C/s[/tex]

Here  I means current

    The time interval is [tex]t=100 \mu s  = 100*10^{-6}[/tex]

Generally the amount of charge is mathematically represented as

        [tex]Q =  \frac{I}{t}[/tex]

=>      [tex]Q =  \frac{20000}{ 100*10^{-6}}[/tex]

=>    [tex]Q =  2.0*10^8 \  C[/tex]

The number of electrons that flow during that time is evaluated as

    [tex]N  =  \frac{Q}{e}[/tex]

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

So

         [tex]N  =  \frac{2.0*10^8}{ 1.60*10^{-19}}[/tex]

         [tex]N  =  1.25 *10^{27} \  electrons[/tex]

Answer:

Aerobic physical activity is better for the cardiovascular system than it is for strength endurance, while anaerobic physical activity is better at building strength endurance than it is at increasing cardiorespiratory fitness.

Therefore true

Given :

Distance of point P from the origin is , d = 9.83 mm .

To Find :

The electric field produced by this charge at point P , if charge is placed at origin .

Solution :

Let , charge on origin is q .

Electric field at point P is given by :

[tex]E=\dfrac{kq}{r^2}[/tex]    ..... ( 1 )

Here , k is constant , [tex]k=9\times 10^{9}\ N \ m^2/C^2[/tex] .

Putting value of k and r in above equation , we get :

[tex]E=\dfrac{q\times 9\times 10^9}{(9.83\times 10^{-3})^2}\ N/C\\\\E=(9.31\times 10^{13})q\ N/C[/tex]

Hence , this is the required solution .

Answer:

50.2m/s

Explanation:

Using first equation of motion we have

V= u+gt

V= final speed

U= initial speed

So v = 1.2m/s + 9.8(5s)

50.2m/s