Explanation:
B. Doubling the heat flow into the engine while halving the work done
hope this helps you
have a nice day
6
A light bulb changes
???? energy into
and ??? energy
The
??? energy is useful energy, and the heat energy is ??
energy
Explanation:
electrical energy into heat energy
electrical , thermal
A bullet with a mass mb=13.5 g is fired into a block of wood at velocity vb=245 m/s. The block is attached to a spring that has a spring constant k of 205 N/m. The block and bullet continue to move, compressing the spring by 35.0 cm before the whole system momentarily comes to a stop. Assuming that the surface on which the block is resting is frictionless, determine the mass mw of the wooden block.
Momentum is conserved, so the sum of the momenta of the bullet and block before collision is equal to the momentum of the combined bullet-block system,
[tex]m_bv_b+m_wv_w = (m_b+m_w)v[/tex]
where v is the speed of the bullet-block system. The block starts at rest so it has no initial momentum, and solving for v gives
[tex]v = \dfrac{m_b}{m_b+m_w} v_b[/tex]
The total work W performed by the spring on the bullet-block system as it is compressed a distance x is
[tex]W = -\dfrac12kx^2[/tex]
where k is the spring constant, and the work done is negative because the restoring force of the spring opposes the bullet-block as it compresses the spring.
By the work-energy theorem, the total work done is equal to the change in the bullet-block's kinetic energy ∆K, so we have
[tex]W_{\rm total} = W = \Delta K[/tex]
The bullet-block starts moving with velocity v found earlier and comes to a stop as the spring slows it down, so we have
[tex]-\dfrac12kx^2 = -\dfrac12(m_b+m_w)v^2 \implies kx^2 = \dfrac{{m_b}^2}{m_b+m_w}{v_b}^2[/tex]
Solve for [tex]m_w[/tex]:
[tex]m_w=\dfrac1k\left(\dfrac{m_bv_b}x\right)^2-m_b[/tex]
[tex]m_w=\dfrac1{205\frac{\rm N}{\rm m}}\left(\dfrac{(0.0135\,\mathrm{kg})\left(245\frac{\rm m}{\rm s}\right)}{0.350\,\rm m}\right)^2-0.0135\,\mathrm{kg}\approx \boxed{0.422\,\mathrm{kg}}[/tex]
Water has a specific heat of 4.186 J/g°C, and ethanol has a specific heat of 2.450 J/g°C. Based on this information, which best compares water and ethanol?
The question is incomplete, the complete question is;
Water has a specific heat of 4.186 J/g°C, and ethanol has a specific heat of 2.450 J/g°C. Based on this information, which best compares water and ethanol?
It requires more heat to raise the temperature of a gram of ethanol by 1°C.
There are more molecules in a gram of water.
Ethanol has a lower formula mass.
Water has more protons and neutrons in its nuclei.
Answer:
There are more molecules in a gram of water.
Explanation:
Let us recall that the molar mass of water is 18g/mol while the molar mass of ethanol is 46 g/mol.
Hence;
1 g of water contains 18 g
There are 6.02 × 10^23/18g = 3.34 × 10^22 molecules in 1 g of water
1 g of ethanol contains 46 g
There are 6.02 × 10^23/46 g = 1.31 ×10^22 molecules
Hence, there are more molecules in 1 g of water than in 1g of ethanol.
Answer:
there are more molecules in 1 g of water than in 1g of ethanol.
Explanation:
edge 23
Calculate the acceleration of a bus that speed up from 20ms-1 to 40ms-1 in 8 seconds?
Answer:
2.5 ms^-2
Explanation:
acceleration
= (final velocity - initial velocity)/time
= [(40m/s) - (20m/s)]/8s
= (20m/s)/8s
= 5/2 m/s²
= 2.5 m/s²
= 2.5 ms^-2
3. A microwave oven draws 12 A of current on a 110 V household circuit. What is its power
rating?
Answer:
W = 1320Watts
Explanation:
W = I*V
W = 12A*110V
W = 1320Watts
This happens because the.....particles are most likely to escape from the liquid, causing the temperature of the liquid to.....
Answer:Boiling
Explanation: If a liquid is heated the particles are given more energy and move faster and faster expanding the liquid. The most energetic particles at the surface escape from the surface of the liquid as a vapour as it gets warmer.
Define electric current and drift velocity.
Answer:
Explanation: The voltage or potential difference between two points is defined to be the change in ... I = qnAv relates the drift velocity to the current
How many atoms are in the compound NaNO3?
Explanation:
3 atoms are in the compound
Un muelle se alarga 20 cm cuando ejercemos sobre él una fuerza de 24 N. Calcula:El valor de la constante elástica del muelle
Answer:
120 Nm-1
Explanation:
Según la ley de Hooke;
F = Ke
F = fuerza sobre el resorte
K = constante de fuerza
e = extensión
Por eso;
K = F / e
K = 24N / 20 × 10 ^ -2m
K = 120 Nm-1
You are pulling a sled using a horizontal rèpe, as shown in the diagram. The rope pulls the sled. exerting a force of 50 N to the right. The snow exerts a friction force of 30 N on the sled to the left. The mass of the sled is 50 kg.
Please help me with this
Answer:
Explanation:
From your other post, the complete question is:
"You are pulling a sled using a horizontal rèpe, as shown in the diagram. The rope pulls the sled. exerting a force of 50 N to the right. The snow exerts a friction force of 30 N on the sled to the left. The mass of the sled is 50 kg.
Find the sum of the force on the sled.
Determine the acceleration of the sled .
If the sled has an initial velocity 2m/s to the right, how fast will it be traveling after 5 seconds?
"
Given the rope exerting a force of 50 N to the right and the snow exerts a friction force of 30 N to the left, the sum of forces
= 50 - 30
= 20N to the right
The mass of sled is 50 kg and force = mass * acceleration.
Acceleration = Force / mass
= 20 / 50 = 0.4 m/s^2 to the right
If the sled has an initial velocity 2m/s to the right, after 5 seconds it will be traveling at initial velocity + acceleration * time
= 2 + 0.4*5
= 4 m/s to the right
Answer:
Explanation:
net force = applied force - friction force
= 50-30
= 20N to right
acceleration = net force/mass
= 20/50
= 2/5m/s tp right
final velocity = initial velocity + acceleration*time
= 2+2/5*5
= 4m/s to right
What do you mean by unit?
Unit is the quantity of a constant magnitude which is used to measure the magnitudes of other quantities of the same nature.
Answer:
The standard known quantity which is used to measure a physical quantities is known as unit.
Kgms-1-= Ns ...solution
Answer:
units of impact or impulse or momnetum are same
These are
Kg m s-1 or N s
A rabbit runs a distance of 60 meters in 20s. What is the average speed?
Answer:
3 m/s
Explanation:
Given,
Total distance = 60 m
Total time = 20 s
We know that,
Average speed = Total distance/Total time
=> Average speed = 60 m/20 s
=> Average speed = 3 m/1 s
=> Average speed = 3 m/s
Average speed=Total distance/Total time
[tex]\\ \sf\longmapsto Average\:Speed=\dfrac{60}{20}[/tex]
[tex]\\ \sf\longmapsto Average\:Speed=3m/s[/tex]
What does vitamin c do for our body?
Answer:
necessary for the growth, development and repair of all body tissues. it's involved in many body functions, including formation of collagen, absorption of iron, the proper functioning of the immune system, wound healing, and the maintenance of cartilage, bones, and teeth.
Explanation:
Answer:
Vitamin C act as antioxidant which protect our cell from damaging caused by radicals.
if you add km/ hr with another km/ hr what will you get
Answer:
km/hr
Explanation:
Addition and subtraction are commutative
Meaning you can add or subtract in any order because it doesn't change the sum or the difference. So it doesn't change the units.
Answer:
km/ hr + km/ hr =(km+ km)/hr=2km/hr
Explanation:
Please help! Will mark Brainliest.
Answer:
18 Nm
Explanation:
if the correct answer
1.slope of distance time graph gives______in the case of uniform motion.
2.The magnitude of velocity and______will be equal if motion is along a straight path.
the first one answer is speed and the second one is direction.
Answer:
1. Slope of distance time graph gives Speed in the case of uniform motion
2.The magnitude of velocity and Displacement will be equal if motion is along a straight path
Explanation:
PLEASE MARK BRAINLEST
Define measurement and write its importance.
Answer:
Measurement is the way humans define certain amounts of matter, and is expressed in various types of units respective to the type of matter or object being defined.
Explanation:
Measurement is extremely important because it helps one another understand how much of something is needed to accomplish something. If no method existed to define the specific amount needed, we would simply mess delicate operations up and machines, even simple recipes, would fail.
How do longshore currents shape the land?
Answer:
Longshore drift has a very powerful influence on the shape and composition of the coastline. It changes the slopes of beaches and creates long, narrow shoals of land called spits, that extend out from shore. Longshore drift may also create or destroy entire “barrier islands” along a shoreline.
In which instrument of the following the water works as a bulb
Answer:
hydrometer
Explanation:
A hydrometer is an instrument used to determine specific gravity. It operates based on the Archimedes principle that a solid body displaces its own weight within a liquid in which it floats. Hydrometers can be divided into two general classes: liquids heavier than water and liquids lighter than water.
a car moves at a speed of 40km/h. it is stopped by applying brake which produce a uniform acceleration of-0.5m/s^2. how much distance will it move before coming to stop ? plz its urgent
Answer:
Explanation:
I answered this in question #24313516
How many valence electrons does each atom of arsenic (As) have? Arsenic is element 33. It is in period 4 and family 15 (5A or the Nitrogen family).
(1 point)
15
33
5
4
Answer:5
Explanation:
Mass of the sun is 2x10³⁰ kg and that of the earth is 6/10²⁴ kg and the distance between them is 1.5 x 10¹¹m. What is the gravitational force produced between them?
Answer:
The gravitational force is 3.56 × 10^22 N
Explanation:
[tex]{ \bf{force = \frac{GM_{s} m _{e}}{ {r}^{2} } }}[/tex]
[tex]{ \sf{force = \frac{6.67 \times {10}^{ - 11} \times (2 \times {10}^{30} ) \times (6\times {10}^{24}) }{(1.5 \times {10}^{11}) {}^{2} } }} \\ \\ { \sf{force = 3.56 \times {10}^{22} \: newtons}}[/tex]
Help quick
How does the ramp produce mechanical advantage?
A it reduces the amount of input force needed to do a certain amount of work
B it reduces the distance over which the input force needs to be applied
C it reduces the amount of useful work done on objects move it up the ramp
D what is the overall amount of work done on object moving up the ram
C it reduces the amount of useful work done on objects move it up the ramp
How much power does it take to lift a box with a weight of 50N to put it on a shelf that is 10m high in
10 sec?
We know
[tex]\boxed{\sf Power=\dfrac{Work\:done}{Time}}[/tex]
[tex]\\ \sf\longmapsto Power=\dfrac{Force\times displacement}{Time}[/tex]
[tex]\\ \sf\longmapsto Power=\dfrac{50\times 10}{10}[/tex]
[tex]\\ \sf\longmapsto Power=\dfrac{500}{10}[/tex]
[tex]\\ \sf\longmapsto Power=50W[/tex]
SHOW REFRACTION THROUGH A GLASS SLATE WITH NEAT DIAGRAM
[tex] \: \: \: \: \: \: \: \: \: \: \: I \: need \: answer \: [/tex]
Refer to the attachment
Which class of lever has all advantages of lever
Answer:
Helo ....
so this answer would be First class levers
becoz...
First-class levers have a considerable practical advantage over the other types of levers. They convert a downward moving force into a lifting force
is it possible to mark it brainliest <3
Can someone help me please this test is very important
Answer:
Friction is caused in roller coasters by the rubbing of the car wheels on the track and by the rubbing of air (and sometimes water!) against the cars.
Explanation:
28 Why is soft iron used for the core of an electromagnet?
А Soft iron easily becomes a permanent magnet.
B Soft iron is a good electrical conductor.
с Soft iron is a poor thermal conductor.
D Soft iron loses its magnetism when the current in the coil is switched off.
Answer:
An electromagnet is a form of magnet that is made by the passage of electric current through a coil of wire. The core of an electromagnet increases the strength of the produced magnetic field
Soft iron is used as the core of an electromagnet because soft iron is a magnetic material and therefore it is permeable to and becomes magnetized by the magnetic field coming from the flowing current, thereby allowing more flux to pass through the core of the electromagnet, producing a magnetic field strength that is several times that of an air core electromagnet as the relative permeability (to magnetic flux, compared to vacuum) of soft iron is about 64 × 10³
However, once the current is switched, the soft iron does not remain its magnetic, and therefore, the electromagnet becomes demagnetized, thereby being able to maintain its electromagnetic characteristics (being made magnetic by the flow of electric current)
Explanation:
The hair dryer has a plastic case so there is no need for an earth wire connection in the plug ,explain why the hair dryer is still safe to use.
Answer:
plastics are unable to conduct electricity and heat due to there being no free flowing electrons, meaning they are safe to use.
Explanation:
