Answer:
D) 0.32
Explanation:
The computation of the thermal efficiency is given below:
Thermal efficiency is
= 710 J ÷ (710 J + 1480 J)
= 710 J ÷ 2,190 J
= 0.32
Hence, the thermal efficiency is 0.32
Therefore the last option is correct
Mechanical Advantage!
Need help fast.
THE RIGHT ANSWER WILL RECEIVE A BRAINLESS AND POINTS AND THANKS!!! THE RIGHT ANSWER WILL RECEIVE A BRAINLESS AND POINTS AND THANKS!!! What is the fundamental frequency of a mandolin string that is 42.0 cm long when the speed of waves of the string is 329 m/s? with working outs
Answer:
[tex]f_{o}[/tex] = 391.67 Hz
Explanation:
The sound of lowest frequency which is produced by a vibrating sting is called its fundamental frequency ([tex]f_{o}[/tex]).
The For a vibrating string, the fundamental frequency ([tex]f_{o}[/tex]) can be determined by:
[tex]f_{o}[/tex] = [tex]\frac{v}{2L}[/tex]
Where v is the speed of waves of the string, and L is the length of the string.
L = 42.0 cm = 0.42 m
v = 329 m/s
[tex]f_{o}[/tex] = [tex]\frac{329}{2*0.42}[/tex]
= [tex]\frac{329}{0.84}[/tex]
[tex]f_{o}[/tex] = 391.6667 Hz
The fundamental frequency of the string is 391.67 Hz.
Lightning McQueen races with an average speed of 125 miles per hour. He drives 400 miles in a
race, how much time does it take him to complete the race?
Please help 20 points!!!!
Answer:
3.2 hours
Explanation:
400÷125=3.2
3.2 or 3 hours and 12 minutes.
A 3 kg purple ball moving at 2 m/s to the right collides with a 2 kg white ball at rest. After the collision the purple ball comes to rest (0 m/s). What is the velocity of the white ball after the collision?
Answer:
1.2m/s
Explanation:
Using the law of conservation of energy
m1u1+m2u2 = (m1+m2)v
v is the common velocity after collision
Substitute the given values
3(2) + 2(0) = (3+2)v
6 + 0 = 5v
v = 6/5
v = 1.2m/s
Hence the velocity of the white ball after the collision is 1.2m/s
what energy change takes place when the cell absorbs sunlight
Answer:
It is called photosynthesis.
Explanation:
If the initial speed of the ball was increased, the time of flight of the ball would
1) decrease 2) increase 3) remain the same
Answer:2 increase
Explanation:
The ________________of an element is the average mass of the element’s ____________________.
Answer:
The average atomic mass (sometimes called atomic weight) of an element is the weighted average mass of the atoms in a naturally occurring sample of the element. Average masses are generally expressed in unified atomic mass units (u), where 1 u is equal to exactly one-twelfth the mass of a neutral atom of carbon-12.(I hope this helps!)
Use the drop-down menus to complete the sentences describing what happens when the temperature of a fluid
ncreases.
The kinetic energy of the molecules
The speed of the molecules
The density of the fluid
The fluid
Answer:
The kinetic energy of the molecules increases as it heats up causing it to vibrate faster and faster.
Explanation:
Determine the thrust that a boat with a volume of 1.2m³ receives when it is stranded at sea. The density of seawater is 1020kg / m³.
Answer:
The maximum possible up-thrust on the boat is 11,995.2 N
Explanation:
According to Archimedes' principle, the thrust received by an object immersed a fluid is equal to the weight of the fluid displaced;
The given parameter of the boat in sea water are;
The volume of the boat = 1.2 m³
The density of seawater = 1020 kg/m³
Density = Mass/Volume
Therefore, Mass = Density × Volume
The maximum volume of water that the boat displaces = 1.2 m³
The mass of the water displaced by the boat = (Density of seawater) × (Volume of seawater displaced)
∴ The maximum possible mass of the water displaced by the boat = 1.2 m³ × 1020 kg/m³ = 1224 kg
The maximum possible mass of the water displaced by the boat, m = 1224 kg
Weight = Mass, m × g
Where;
g = The acceleration due to gravity = 9.8 m/s²
The up-thrust on the boat = The weight of the seawater displaced
∴ The maximum possible up-thrust on the boat = m × g = 1224 kg × 9.8 m/s² = 11,995.2 N
The maximum possible up-thrust on the boat = 11,995.2 N.
A man of weight Wman is standing on the second floor and is pulling on a rope to lift a box of weight Wbox from the floor below. The rope, which is of negligible weight, has tension T in it, but the pull of the rope is insufficient to lift the box off the floor. What is the magnitude of the normal force that the second floor exerts on the man in this situation?
Answer:
Explanation:
See the attached figure . See the forces acting on man pulling up the box .
Man is stationary so net force acting on man is zero .
T + R = Wman
R is the reaction force of the ground of second floor .
R = Wman - T
you are on a walk moving at 3m/s forward what would happen i you stepped off onto the floor? what if you stepped onto another walkaway moving with the same velocity?
Answer:
1) The person ma tend to fall
2) The person will remain upright
Explanation:
1) According to Newton's first law of motion, an object will continue in its state of rest or maintain its uniform motion on a straight line unless acted on by a force
Therefore, when a person steps off onto the floor from a walkway moving at 3 m/s, the friction between the floor and the person's feet prevents the forward motion of the feet, however the person's upper body will tend to continue with the forward motion, and the person may tend to tilt and fall over
2) If the person steps onto another walkway moving with the same velocity, the initial velocity of all parts of the person's body is maintained, such that the person will continue in his uniform motion without experiencing any force and therefore, the person will remain upright
What is the velocity of an object with a mass of 4 kg and a momentum of 24 kg.m/s
Please help
Answer:
6m/s
Explanation:
momentum = mass × change in velocity
∆p =m(v)
24 = 4(v)
V =>24/4 = 6m/s
Cutting down the forest reduces the size of animal habitats, increases erosion, and results in an increase in the amount of carbon dioxide in the atmosphere. In order to stop the harmful effects of cutting down trees, humans can A. clean up litter along the sides of the road. B. clear away the tree trunks and leave the land bare. C. dig up the land and use it as a landfill. D. plant more trees where forests are cut down.
Answer: D. plant more trees where forests are cut down.
Explanation:
Deforestation has to do with the cutting down of trees. Cutting down the forest reduces the size of animal habitats, increases erosion, and results in an increase in the amount of carbon dioxide in the atmosphere.
Ok order to tackle the above, it is necessary that we should plant more trees where forests are cut down.
Help anyone?
Moving causes your muscles to release molecules, which helps process the fats and sugars you eat. If you don't do this, it can cause:
a.
weight gain
b.
heart disease
c.
tight hips
d.
varicose veins
Answer:
A
Explanation:
I thinks is A Im pretty sure its the right answer.
Garen is climbing stairs to the castle. He travels a distance of 350 stairs in 5 minutes of time.
What is his speed?
Please help ASAP!!!
name two types of sound wave
Explanation:
two types of sound wave
transverse wave Longitudinal waveWhat conclusion can be drawn from the fact many of the best international players want to play in the NBA
Answer:
The NBA is a place the best players want to show off their talents at and possibly be very successful.
Explanation:
The players would like fame, the games, and fans that would cheer their name.
Describe the difference between potential and kinetic energy
Answer:
potential energy is the energy possessed by a body by vitue of its possition relative to others stresses with itself electric charge and other factors. kinetic energy is energy which a body possesses by being in motion
Explanation:
hope this helped.have a good day
the graph shows how temperature varies with time as is it heated (not drawn to scale). explain what is happening to the substance in sections AB and BC of the graph
Answer:
The substance is increasing
Hope this helps!
In AB and BC of the graph, the substance is first under the constant temperature condition then under section BC the linear increment in the temperature with the time.
What is a graph ?A graph is a pattern consisting of a collection of elements, some of which are connected in some way.
In the isothermal process, the change in the temperature is zero. While if temperature is increasing along the time, a linear relationship is found.
Hence, in AB and BC section of the graph, the substance is first under the constant temperature condition then under section BC the linear increment in the temperature with the time.
To learn more about the graph, refer to the link;
https://brainly.com/question/14375099
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A stalled car is pushed with a force of 342 N from rest. How far does the car travel in 12 seconds if its mass is 989 kg?
Answer:
Roughly 25 meters
Explanation:
Use the formula D=1/2*a*t^2 where d=distance, a=acceleration, and t=time
Plug in all the variables we know...
D=1/2*a*12^2
in order to solve for acceleration, we use the formula F=ma where F=force, m=mass, and a=acceleration.
Plug in known variables,
342N=989kg*a
solve for a and we get...
342N/989kg=a
Now that we know the acceleration, we can plug that into our original equation and solve for distance.
D=1/2*342N/989kg*12s^2
Simplify,
D=72s^2*342N/989kg
D=72s^2*342kgm/s^2/989kg
D=72s^2*342m/s^2/989
D=72*342m/989
D=24624/989 meters, or 24.898meters which rounds up to 25.
A girl walks 5km due north,then in the direction of 60° of northeast towards her final destination.If the magnitude of her resultant displacement is 8km,how far she must have travelled in north east direction?
Answer:
4.2 km
Explanation:
A triangle is a polygon with three sides and three angles. There are different types of triangles such as isosceles triangle, scalene triangle, equilateral triangle and right angled triangle.
Sine rule states that for a triangle with angles A,B and C and corresponding opposite sides a, b, and c, the following formula holds:
[tex]\frac{a}{sin(A)}=\frac{b}{sin(B)}=\frac{c}{sin(C)}[/tex]
Let the starting point be A, hence the side opposite to the angle = a = distance travelled in north east direction.
Let the point of 60° of northeast be B = 90° + (90° - 60°) = 120°, hence the side opposite to the angle = b = resultant displacement = 8 km.
Let C be the endpoint, hence the side opposite to the angle = c = distance travelled north = 5 km
Using sine rule:
[tex]\frac{b}{sin(B)}=\frac{c}{sin(C)} \\\\\frac{8}{sin(120)}=\frac{5}{sin(C)} \\\\sin(C)=\frac{5*sin(120)}{8} =0.5412\\\\C=sin^{-1}(0.5412)=32.8^o\\\\[/tex]
∠A + ∠B + ∠C = 180° (sum of angle in a triangle)
∠A + 120 + 32.8 = 180
∠A = 27.2°
[tex]\frac{b}{sin(B)}=\frac{a}{sin(A)} \\\\\frac{8}{sin(120)}=\frac{a}{sin(27.2)} \\\\a=\frac{8*sin(27.2)}{sin(120)} \\\\a=4.2\ km[/tex]
Therefore she travelled 4.2 km in the north east direction
How do i calculate the net force of the following question.Plz answer correctly
An object of mass 30 kg is falling in air and experiences a force due to air resistance of 50 newtons.
A)Determine the net force acting on the object and
mass=30 force=50
(a) 50÷30
because we don't have acceleration which is known as m/s2 that stands for meter per seconds square . Hope this help pls follow thank youUsing the picture below, what is the displacement of the triangle?
Answer:
i think it is 40 kilometers in the positive direction... if not im sorry
Explanation:
A 5.1kg iron skillet is heated to 373K from an initial temperature of 295K. How much thermal energy was transferred?
Answer:
the thermal energy transferred is 183,226.68 J
Explanation:
Given;
mass of iron skillet, m = 5.1 kg
initial temperature, t₁ = 295 K
final temperature, t₂ = 373 K
The thermal energy transferred is calculated as;
Q = mcΔt
where;
Δt is change in temperature, = t₂ - t₁
c is specific heat capacity of iron = 460.6 J/kg.K
Q = 5.1 x 460.6 x (373 - 295)
Q = 183,226.68 J
Therefore, the thermal energy transferred is 183,226.68 J
A pitcher throws a 0.145-kg baseball at a velocity of 30.0m/s. How
much kinetic energy does the ball have?
Answer: 65.25 J
Explanation:
Kinetic Energy K.E. = 1/2 * m * v^2 ; where m is the mass of the body and v is the velocity of the body ; K.E. = 1/2 * 0.145 * 30 * 30 = 65.25 Joules
A large, heavy cargo container is taken from the surface of the Earth and
brought to the Moon to begin building a base camp. What is MOST different
about this cargo container on the Moon?
a
b
On the Moon, the cargo container has a different volume.
On the Moon, the cargo container has a different shape.
On the Moon, the cargo container has a different mass.
On the Moon, the cargo container has a different weight.
с
d
Answer:
D
Explanation:
A different weight
paper by itself catches fire easily whereas a piece of paper wrapped around an alluminium pipe does not.
Answer:
The paper does not catch fire when wrapped around aluminium pipe because aluminium absorbs the heat, so paper does not attain its ignition temperature.
Explanation:
on what factors do pressure depend
Answer:
*pressure of solid depends on:
1/Magnitude of the force.
2/contact area.
*pressure of liquid depends on:
1/Depth inside the fluid.
2/density of the fluid.
3/Acceleration due to gravity.
Some knowledge of radioactivity would be useful for understanding which of
the following?
Check all that apply.
A. certain medical procedures
n B. radon in homes
C. rocket boosters on the space shuttle
O D. determining ages of fossils
SUBMIT
Some knowledge of radioactivity would be useful for understanding the certain medical procedures. Option A is correct.
What is radioactivity?The act of producing radiation spontaneously is known as radioactivity. This is accomplished by an unstable atomic nucleus that want to give up some energy in order to move to a more stable form.
Radiation is being employed to assist humanity in medical, academia, and industry, as well as to generate power.
Radiation is also important in agriculture, archaeology, space exploration, law enforcement, geology a variety of other fields.
Some knowledge of radioactivity would be useful for understanding the certain medical procedures.
Hence, option A is correct.
To learn more about the radioactivity, refer to the link;
https://brainly.com/question/1770619
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When solid (S1) is heated, it breaks up into a gas (G) and another solid (S2). All three of these chemicals are pure substances. On the basis of this information alone, which of these must be compounds? Why?
Answer:
S1
Explanation:
Has to be S1. This is pretty glaring to me. It's said from the question that the chemical reaction that took place is given by the following
S1 + G = S2, with S2 being an offspring of the first S1. When S1 got reacted, it broke down into S2, so, this only confirms that both S1 and E2 are S3 are compounds.