Answer:
Option A. 40 mi/h
Explanation:
To obtain the average speed of the vehicle, we'll begin by calculating the distance travelled by the vehicle in each case. This is illustrated below:
Case 1:
Speed = 30 mi/h
Time = 2 h
Distance =...?
Speed = Distance /Time
30 = Distance /2
Cross multiply
Distance = 30 × 2
Distance = 60 mi
Case 2:
Speed = 60 mi/h
Time = 1 h
Distance =...?
Speed = Distance /Time
60 = Distance /1
Cross multiply
Distance = 60 × 1
Distance = 60 mi
Finally, we shall determine the average speed of the vehicle as follow:
Total distance travelled = 60 + 60
Total distance travelled = 120 mi
Total time = 2 + 1
Total time = 3 h
Average speed =..?
Average speed = Total Distance travelled /Total time
Average speed = 120/3
Average speed = 40 mi/h
Therefore, the average speed of the vehicle is 40 mi/h
A two-liter bottle of your favorite beverage has just been removed from the trunk of your car. The temperature of the beverage is 35°C, and you always drink your beverage at 10°C. (a) How much heat energy must be removed from your two liters of beverage (in kJ)? (b) You are having a party and need to cool 10 of these two-liter bottles in one-half hour. What rate of heat removal, in kW, is required? (c) Assuming that your refrigerator can accomplish this and that electricity costs 8.5 cents per kW-hr, how much will it cost to cool these 10 bottles (in $)?
Answer:
a) 209.3 kilojoules must be removed from two liter of beverage, b) A rate of heat removal of 1.163 kilowatts is required to cool down 10 2-liter bottles, c) Cooling 10 2-L bottles during 30 minutes costs 4.9 cents.
Explanation:
a) How much heat energy must be removed from your two liters of beverage?
At first we suppose that the beverage has the mass and specific heat of water and that there are no energy interactions between the bottle and its surroundings.
From the First Law of Thermodynamics and definition of sensible heat, we get that amount of removed heat ([tex]Q[/tex]), measured in kilojoules, is represented by the following formula:
[tex]Q = \rho \cdot V\cdot c\cdot (T_{o}-T_{f})[/tex] (Eq. 1)
Where:
[tex]\rho[/tex] - Density of the beverage, measured in kilograms per cubic meter.
[tex]V[/tex] - Volume of the bottle, measured in cubic meters.
[tex]c[/tex] - Specific heat of water, measured in kilojoules per kilogram-Celsius.
[tex]T_{o}[/tex], [tex]T_{f}[/tex] - Initial and final temperatures, measured in Celsius.
If we know that [tex]\rho = 1000\,\frac{kg}{m^{3}}[/tex], [tex]V = 2\times 10^{-3}\,m^{3}[/tex], [tex]c = 4.186\,\frac{kJ}{kg\cdot ^{\circ}C}[/tex], [tex]T_{o} = 35\,^{\circ}C[/tex] and [tex]T_{f} = 10\,^{\circ}C[/tex], then:
[tex]Q = \left(1000\,\frac{kg}{m^{3}}\right)\cdot (2\times 10^{-3}\,m^{3})\cdot \left(4.186\,\frac{kJ}{kg\cdot ^{\circ}C} \right) \cdot (35\,^{\circ}C-10\,^{\circ}C)[/tex]
[tex]Q = 209.3\,kJ[/tex]
209.3 kilojoules must be removed from two liter of beverage.
b) You are having a party and need to cool 10 of these two-liter bottles in one-half hour. What rate of heat removal, in kW, is required?
The total amount of heat that must be removed from 10 2-L bottles is:
[tex]Q_{T} = 10\cdot (209.3\,kJ)[/tex]
[tex]Q_{T} = 2093\,kJ[/tex]
If we suppose that bottles are cooled at constant rate, then, rate of heat removal is determined by this formula:
[tex]\dot Q = \frac{Q_{T}}{\Delta t}[/tex] (Eq. 2)
Where:
[tex]Q_{T}[/tex] - Total heat, measured in kilojoules.
[tex]\Delta t[/tex] - Time, measured in seconds.
[tex]\dot Q[/tex] - Rate of heat removal, measured in kilowatts.
If we know that [tex]Q_{T} = 2093\,kJ[/tex] and [tex]\Delta t = 1800\,s[/tex], we find that rate of heat removal is:
[tex]\dot Q = \frac{2093\,kJ}{1800\,s}[/tex]
[tex]\dot Q = 1.163\,kW[/tex]
A rate of heat removal of 1.163 kilowatts is required to cool down 10 2-liter bottles.
c) Assuming that your refrigerator can accomplish this and that electricity costs 8.5 cents per kW-hr, how much will it cost to cool these 10 bottles (in $)?
A kilowatt-hour equals 3600 kilojoules. The electricity cost is equal to the removal heat of 10 bottles ([tex]Q_{T}[/tex]), measured in kilojoules, and unit electricity cost ([tex]c[/tex]), measured in US dollars per kilowatt-hour. That is:
[tex]C = c\cdot Q_{T}[/tex]
If we know that [tex]c = 0.085\,\frac{USD}{kWh}[/tex] and [tex]Q_{T} = 2093\,kJ[/tex], the total cost of cooling 10 bottles is:
[tex]C = \left(0.085\,\frac{USD}{kWh}\right)\cdot \left(2093\,kJ\right)\cdot \left(\frac{1}{3600}\,\frac{kWh}{kJ} \right)[/tex]
[tex]C = 0.049\,USD[/tex]
Cooling 10 2-L bottles during 30 minutes costs 4.9 cents.
how does a fly function in a energy pyramid
Answer:
A pyramid of energy shows the relative amount of energy available at each trophic level of a food chain or web. On average, about 10 percent of the energy available within one trophic level is transferred to the next level.
Explanation:
If you walk North for 40 feet and then walk East for 30 feet, what is your total distance
travelled? What is your displacement?
Answer:
The person travelled a total distance of (40+30) feet = 70 feet
Displacement= 50feet (im not positive on the displancement)
displacemeny is the shortest distance between two pionts
Explanation:
Which is the correct answer? Please help.
Answer:
i believe it is c
Explanation:
hope this helps and plz mark brainliest
A roller coaster at the Six Flags Great America amusement park in Gurnee, Illinois, incorporates some clever design technology and some basic physics. Each vertical loop, instead of being circular, is shaped like a teardrop. The cars ride on the inside of the loop at the top, and the speeds are fast enough to ensure that the cars remain on the track. The biggest loop is 40.0 m high. Suppose the speed at the top is 10.8 m/s and the corresponding centripetal acceleration is 2g. (a) What is the radius of the arc of the teardrop at the top
Answer:
5.95 m
Explanation:
Given that the biggest loop is 40.0 m high. Suppose the speed at the top is 10.8 m/s and the corresponding centripetal acceleration is 2g
For the car to stick to the loop without falling down, at the top of the ride, the centripetal force must be equal to the weight of the car. That is,
(MV^2) / r = mg
V^2/ r = centripetal acceleration which is equal to 2g
2 × 9.8 = 10.8^2 / r
r = 116.64 /19.6
r = 5.95 m
What Health Related Component of Physical Fitness is the ability of the heart and lungs to supply oxygen to the body? a. Muscular Strength c. Cardiorespiratory Endurance b. Muscular Endurance d. Flexibility
PLEASE HELP!!!! Which is the best example of a non-inertial frame of reference? (1 point)
A. a roller coaster maintaining its speed as it curves around a bend
B. a falling feather in which the upward force due to air resistance equals the force of gravity
C. a spaceship traveling at 947 m/s with its engines off
D. a boat at rest on calm water
Answer: B
Explanation:
A - No, because this has nothing to do with curves
B - Yes, because it explains gravity and it it forced down by gravity
C - No, because this has nothing to do with a rocket ship an dhow much it can travel per #.
D - No, because This has nothing to do with a boat on water and it explain nothing about gravity or how fast it is.
I Hope This Helped!
Answer:a roller coaster maintaining its speed as it curves around a bend
Explanation: gradpont
Being a micro-manager is an example of using effective team building techniques
T or F
Answer:
TRUE
Explanation:
Answer:
True
Explanation:
Two forces are described below:
Force 1: The squeezing force applied to remove water from a wet cloth
Force 2: The gravitational force exerted by Earth on the moon
Which statement is true about the forces? (3 points)
Both are contact forces.
Both are non-contact forces.
Force 1 is a non-contact force and Force 2 is a contact force.
Force 1 is a contact force and Force 2 is a non-contact force.
Answer:
its Force 1 is a contact force and Force 2 is a non-contact force.
Explanation:
I took the test!
Answer:
Force 1 is a contact force, Force 2 is a non-contact force :)
Explanation:
Because Force 1 is an object touching something and Force 2 is a force that is not touching something (hope this helps)
(QUICK THIS IS DUE IN FIVE MINUTES) Please select A, B, or C
Answer:
a
Explanation:
Answer:
A
Explanation:
In deriving the axial electric field for the ring-shaped charge distribution and the electric field from a long line of charge, the component perpendicular to the resulting field is zero because of what physical property? In deriving the axial electric field for the ring-shaped charge distribution and the electric field from a long line of charge, the component perpendicular to the resulting field is zero because of what physical property? positive and negative charges cancel symmetry only net charge is important superposition integration
Answer:
d)symmetry
Explanation:
Here is the complete question
In deriving the axial electric field for the ring-shaped charge distribution and the electric field from a long line of charge, the component perpendicular to the resulting field is zero because of what physical property? Answer a)integration b)superposition c)only net charge is important d)symmetry e) positive and negative charges cancel
Solution
The perpendicular components of the resulting electric field is zero because of symmetry since the charge is evenly distributed around the ring or line of charge. At one point, there is an electric field dE due to a small charge element dq and a corresponding electric field dE' due to a small charge element dq' opposite to dq.
Since the charges are symmetrical about the center, the horizontal (or perpendicular) components of the electric fields would cancel out causing the horizontal component of the resulting electric field to be zero.
So, the perpendicular component of the resulting electric field is zero due to symmetry.
Which two types of waves require matter in order to travel A:light waves B:sound waves C:electromagnetic waves D:Water waves
Answer:
Sound Waves
Light Waves
Explanation:
Which example illustrates Newton's second law?
Answer:
Newtons third law states, "The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object."
Explanation:
an illustration of this would probably be a missile.
Answer: C. “More mass is added to a wheelbarrow remains, and larger forces required to move it”
Lien is pushing a box across a table. She used a force of 100 N to get the box moving. Which force did she overcome
to get the box moving?
O the downward force of gravity on the box
O the upward force of the table on the box
the reaction force on the box
O the push force on the box
Answer:
the reaction force on the box
Explanation:
In order to push or pull an object, an external force is needed to overcome the weight of that object. This force is called ACTION FORCE. However, according to 3rd law of Newton, which states that for every action, there is an equal and opposite reaction, an opposite force counters the object in an opposite direction. This force is called REACTION FORCE.
According to this question, Lien is pushing a box across a table. She used a force of 100 N to get the box moving. This means that she had to overcome an opposite force called REACTION FORCE, with an ACTION FORCE of 100N
Answer:
C. the reaction force on the box
Explanation:
i literally just finished the quiz
-Cesar the monkey observed the swinging behaviors of his parents. He is now able to swing from branch to branch after much practice. The observation of his parents swinging and practicing what he saw mainly involved _____ neurons; the neurons that are the basis of
Motor
Mirror
Sensory
Reticular
The observation of his parents swinging and practicing what he saw mainly involved sensory neurons.
There are five senses in the human body, they are;
SightSmellTouch TasteHearingInformation is passed to the central nervous system (CNS) from each of these senses.
The neurons that convey sensory information of sight, smell, touch, taste and hearing to the brain are called sensory neurons.
Thus, the observation of his parents swinging and practicing what he saw mainly involved sensory neurons.
Learn more: https://brainly.com/question/9911075
Which undergoes greater acceleration: an airplane that goes from 1000 km/h to 1005 km/h in 10 seconds or a skateboard that
goes from zero to 5 km/h in 1 second?
Answer:
Skateboard
Explanation:
Acceleration is change in velocity over time.
a = Δv / Δt
The airplane's acceleration is:
a = (1005 km/h − 1000 km/h) / 10 s
a = 0.5 km/h/s
The skateboard's acceleration is:
a = (5 km/h − 0 km/h) / 1 s
a = 5 km/h/s
What was the instantaneous speed of Bear A at 5 seconds in meters/min? (No unit conversions necessary, no units required for answer. Type your answer.)
Answer: The answer is 40.
Explanation: There is a typo, they mean 5 minutes. Five minutes is the line between zero and 10, and the dot matches up at 5 and 200. 200 divided by 5= 40.
A single-slit diffraction pattern is formed on a distant screen. Assuming the angles involved are small, by what factor will the width of the central bright spot on the screen change if the slit width is doubled? A single-slit diffraction pattern is formed on a distant screen. Assuming the angles involved are small, by what factor will the width of the central bright spot on the screen change if the slit width is doubled? It will be cut in half. It will double. It will become eight times as large. It will be cut to one-quarter its original size. It will become four times as large.
Answer:
It will be cut in half
Explanation:
The diffraction of a slit is given by the formula
a sin θ = m where
a = width of the slit,
λ = wavelength and
m = integer that determines the order of diffraction.
Next we divide both sides by a, we have
sin θ = m λ / a
Also, recall that
a’ = 2 a
Then we substitute in the previous equation
2asin θ' = m λ, if divide by 2a, we have
sin θ' = (m λ / 2a).
Now again, from the first equation, we said that sin θ = m λ / a, so we substitute
sin θ ’= sin θ / 2
Then we use trigonometry to find the width, we say
tan θ = y / L
Since the angle is small, we then have
tan θ = sin θ / cos θ
tan θ = sin θ, this then means that
sin θ = y / L
we will then substitute
y’ / L = y/L 1/2
y' = y / 2
this means that when the slit width is doubled the pattern width will then be halved
Which direction is the force of gravity on earth
Answer:
It is toward the center
Explanation:
What is the example of stop moving
Answer:
Example:
A car applying brake.
A player catching a bowl.
What indicates that an object has been subjected to an unbalanced force?
A father fashions a swing for his kids out of a long rope that he fastens to the limb of a tall tree. As one of the kids swings from this rope that is 7.00 m long his tangential speed at the bottom of the swing is 8.65 m/s. What is his angular speed in rad/s
Answer:
1.236 rad/s
Explanation:
From the question above,
v = ωr................ Equation 1
Where v = tangental speed, ω = angular speed, r = radius = length of the rope.
Make ω the subject of the equation
ω = v/r.............. Equation 2
Given: v = 8.65 m/s, r = 7.00 m
Substitute these values into equation 2
ω = 8.65/7
ω = 1.236 rad/s
Hence the angular speed is 1.236 rad/s
An airplane has a maximum airspeed velocity of 140 mph South. If the wind is 60 mph West, what is the resultant velocity (groundspeed) and direction of the airplane?
Answer:
R∠ is 152,3 ∠ 246,8
Explanation:
We need to add (vectorially) these two velocities. We can choose the coordinates system just that speed of the airplane is the negative part of the y-axis, and negative region of the x-axis, for wind speed, according to
this, the module of the resultant velocity R is:
R =√ (60)² + (140)²
R = √( 3600) + ( 19600)
R =√ 23200
R = 152,315 mph
The tangent of the angle (α ) between R and the y-axis is:
tan α = 60/140
tan α = 0,4286
From tangent tables, we get arctan 0.4286
α = 23,2⁰
Then R∠ is 152,3 ∠ 246,8
Answer:
R∠ is 152,3 ∠ 246,8
I WILL MARK YOU AS BRAINLIEST IF RIGHT
A 2300 kg bus travels 15 miles in 0.75 hours . What is the average speed of the bus?
what is 25.61 cm to Gm?
Explanation:
25.61 cm * 1 Gm
100000000000 cm = 2.561e-10 Gm
1 Gm = 10^9 m =10^11 cm
then 10^11 cm = 1Gm
25.61 cm = 25.61 /10^11
=25.61 * 10^-11 Gm
What element has similar chemical properties to lodine?*
Answer:
Iodine is most similar to the other non- metals in the Halogen Family, such as Fluorine, Chlorine, Bromine, Astatine .
Explanation:
A plane drops a package for delivery. The plane is flying horizontally at
a speed of 110 m/s, and the package travels 550 m horizontally during
the drop. We can ignore air resistance. What is the packages vertical
displacement during the drop?
Answer:
122.5m.
Explanation:
I think it's right..
Two charged objects, A and B, are exerting an electric force on each other. What will happen if the charge on A is increased?
А. The charge on B will decrease.
В. The charge on B will increase.
C. The electric force between A and B will decrease.
D. The electric force between A and B will increase.
Answer: The forces acting on both of them will increase in magnitude.
Explanation:
According to Coulomb's law, the electrostatic force between two bodies is proportional to the product of their two charges. If the charge on A is increased this product increases in size (it must have been non-zero to begin with, since there was a force between them at first). Thus, the force between them rises.
Answer:
d. seems like the right answer.
Explanation:
please please please please please please
9514 1404 393
Answer:
Mona
Explanation:
Speed is the slope of the position vs. time curve. The higher speed will have the greater slope.
Mona's curve has a greater slope, so Mona is fastest.
17
Drag the tiles to the correct boxes to complete the pairs.
Match each interaction with its example.
commensalism
mutualism
parasitism
competition
Giardia lamblia, a microorganism, invades the cells of the small intestine in humans,
absorbs nutrients, and causes diarrhea in its host.
Ants protect aphids from their predators, ladybugs, in return for honeydew.
Two species of grass in an ecosystem require water and the same nutrients.
A barnacle attaches to a whale for transport, but does not affect the whale.
Reset
Next
Answer:
Giardia lamblia, a microorganism, invades the cells of the small intestine in humans,
absorbs nutrients, and causes diarrhea in its host is an example of parasitism
Explanation:
Ants protect aphids from their predators, ladybugs, in return for honeydew.is an example of mutualism
Two species of grass in an ecosystem require water and the same nutrients is an example of competition
A barnacle attaches to a whale for transport, but does not affect the whale is an example of commensalism.
Interactions or relationships between organisms can occur where one or both organisms derive benefits from each other.
What are ecological relationships?Ecological relationships are relationships between two or more organisms on how they obtain their food as well as other requirements for survival.
Some feeding relationships include:
commensalismmutualismparasitismcompetitionExamples of the relationships above are:
Parasitusm- Giardia lamblia, a microorganism, invades the cells of the small intestine in humans, absorbs nutrients, and causes diarrhea in its host.Mutualism - Ants protect aphids from their predators, ladybugs, in return for honeydew.Competituon - Two species of grass in an ecosystem require water and the same nutrients.Commensalism- barnacle attaches to a whale for transport, but does not affect the whale.Therefore, relationships between organisms can occur where one or both organisms derive benefits from each other.
Learn more about commensalism and parasitism at: https://brainly.com/question/2437776
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