A sled drops 50 meters in height on a hill. The mass of the rider and sled is 70 kg and the sled is going 10 m/s at the bottom of the hill. What is the efficiency of energy conversion from potential to kinetic?
Answer:
Efficiency = 10.2 %
Explanation:
Given the following data;
Mass = 70 kg
Height = 50 m
Velocity = 10 m/s
We know that acceleration due to gravity is equal to 9.8 m/s².
To find the efficiency of energy conversion from potential to kinetic;
First of all, we would determine the potential energy;
P.E = mgh
P.E = 70 * 9.8 * 50
P.E = 34300 J
For the kinetic energy;
K.E = ½mv²
K.E = ½ * 70 * 10²
K.E = 35 * 100
K.E = 3500
Therefore, Input energy, I = 34300 J
Output energy, O = 3500 J
Next, we find the efficiency;
Efficiency = O/I * 100
Substituting into the formula, we have;
Efficiency = 3500/34300 * 100
Efficiency = 0.1020 * 100
Efficiency = 10.2 %
Un tanque de 50 litros tiene un gas a CNPT. ¿Cuánto valdrá la presión si la temperatura aumenta 40 °C, y el volumen permanece constante?
Answer:
La presion a 40 °C es 1.05 atm.
Explanation:
Usando la ecuación ideal de los gases.
[tex]PV=nRT[/tex]
Debemos recordar, que CNPT significa condiciones normales de presión y temperatura.
Para el primer estado tenemos:
[tex]P_{1}V_{1}=nRT_{1}[/tex]
Donde:
P(1) es la presion en el estado incial (1 atm)V(1) es el volumen incial (50 L)T(1) es la temperatura incial (25 °C = 298 K)Para el segundo estado:
[tex]P_{2}V_{2}=nRT_{2}[/tex]
Donde:
P(2) es la presion en el estado final ( x atm)V(2) es el volumen final (50 L)T(2) es la temperatura final (40 °C = 313 K)Como ambas ecuaciones tienen el mismo valor de volumen podemos igualarlas:
[tex]\frac{nRT_{1}}{P_{1}}=\frac{nRT_{2}}{P_{2}}[/tex]
n y R permanecen constantes, se puden cancelar.
[tex]\frac{T_{1}}{P_{1}}=\frac{T_{2}}{P_{2}}[/tex]
Despejamos P(2).
[tex]P_{2}=\frac{P_{1}T_{2}}{T_{1}}[/tex]
[tex]P_{2}=\frac{1*313}{298}[/tex]
[tex]P_{2}=1.05\: atm[/tex]
Espero te haya sido de ayuda!
Multiple Choice
Which is the best reason to be wary of those you talk to on the Internet?
A. They may not be who they say they are.
B. You don't know where they live.
C. You don't know their favorite foods.
D. They may not be in the same grade as you.
Genes consist portions of _____.
1 7 points If you take less time to perform a task, you have less power output. O True O False
True
The rate at which work is done is referred to as power. A task done quite quickly is described as having a relatively large power. The same task that is done more slowly is described as being of less power. Both tasks require he same amount of work but they have a different power.
A parallel plate capacitor of capacitance Co has plates of area A with separation d between them. When it is connected to a battery of voltage Vo, it has charge of magnitude Qo on its plates. It is then disconnected from the battery and the plates are pulled apart to a separation 2d without discharging them. After the plates are 2d apart, the new capacitance and the potential difference between the plates are: (Show all steps) [2 marks] a. ½ Co, ½ Vo b. ½ Co, 2Vo c. Co, Vo d. Co, 2Vo e. 2Co, 2Vo
Answer:
b. 1/2·C₀, 2·V₀
Explanation:
The capacitance on the parallel plate capacitor = C₀
The area of the plates = A
The voltage on the battery = V₀
The magnitude of the charge on the plate = Q₀
The new distance between the plates = 2·d
From an online physics source, we have;
[tex]C_0 = \epsilon_0 \times \dfrac{A}{d}[/tex]
Where;
ε₀ = Constant
A = The area of the plates
With the new distance, 2·d, we get;
[tex]C_{new} = \epsilon_0 \times \dfrac{A}{2\cdot d} = \dfrac{1}{2} \times \epsilon_0 \times \dfrac{A}{d} = \dfrac{1}{2} \times C_0[/tex]
Therefore;
[tex]The \ new \ capacitance \ C_{new} = \dfrac{1}{2} \times C_0[/tex]
The potential difference, 'V', is given as follows;
[tex]C = \dfrac{Q}{V}[/tex]
Therefore;
[tex]V = \dfrac{Q}{C}[/tex]
Given that Q = Q₀, we get;
[tex]V = \dfrac{Q_0}{\dfrac{1}{2} \times C_0} = 2 \times \dfrac{Q_0}{C_0} = 2 \times V_0[/tex]
∴ V = 2 × V₀
The new potential difference, V = 2·V₀
Therefore, after the plates are 2·d apart, the new capacitance and potential difference between the plates are;
1/2·C₀, 2·V₀.
At a distance of 2d, the potential difference will be twice the potential difference before while the capacitance will be half the value before.
Given to us
The capacitance on the parallel plate capacitor = C₀The area of the plate = AThe voltage on the battery = V₀The magnitude of the charge in the plate = Q₀The new distance between the plates = 2d What is Capacitance?We know capacitance can be written as,
[tex]C= \dfrac{\epsilon_0 A}{d}[/tex]
where C is the capacitance,
A is the area,
d is the distance and
ε₀ is the electrostatic constant,
Capacitance before,[tex]C= \dfrac{\epsilon_0 A}{d}[/tex]
Capacitance Afterwards,[tex]C= \dfrac{\epsilon_0 A}{2d}[/tex]
[tex]C=\dfrac{1}{2} \times \dfrac{\epsilon_0 A}{d}[/tex]
[tex]C=\dfrac{1}{2} \times C_0[/tex]
What is Voltage(Potential difference)?We know that for the voltage we can write,
[tex]\rm Voltage = \dfrac{Charge}{Capacitance}[/tex]
Voltage before[tex]V=\dfrac{Q_0}{C_0}[/tex]
Voltage Afterwards[tex]V_{new} = \dfrac{Q_0}{C_{new}}[/tex]
[tex]V_{new} = \dfrac{Q_0}{\dfrac{1}{2} \times C_0}[/tex]
[tex]V_{new} = 2 \times\dfrac{Q_0}{C_0}[/tex]
[tex]V_{new} = 2 \times V_0[/tex]
Hence, At a distance of 2d, the potential difference will be twice the potential difference before while the capacitance will be half the value before.
Learn more about Capacitance:
https://brainly.com/question/12356566
Two Brothers are playing soccer on the beach. One brother kicks the ball really hard and the ball lands in the water, about 50 meters from the beach. They wonder if the ball will float back to the beach.
Answer:
Due to wind and waves of water.
Explanation:
They wonder that the ball will float back to the beach because of the wind and the waves of the water. The wind blows towards the beach which moves the water in the form of waves towards the beach so if the ball lands in the water, it will floats on the surface of water and move towards the beach with the help of wind and waves of the sea. The ball floats on the water due to its lighter weight and lower density as compared to water.
How does a parallel circuit change when a branch is added?
The total resistance increases, so the current in the circuit decreases.
The total resistance decreases, so the current in the circuit increases.
The total resistance increases, so bulbs shine at a lower brightness.
The total resistance decreases, so bulbs shine at a higher brightne
An element in a similar period to carbon would be
A chlorine
B. hydrogen
C. fluorine
D. magnesium
Answer: C: Fluorine
Explanation:
Carbon is in period two on the periodic table of elements. The only other elements in this period are lithium, borilliym, boron, nitrogen, oxygen, flourine, and neon. Therefore, the answer must be C.
What is the wavelength?
Se dea caer una pelota de basquetbol desde una altura de 90 metros.Calcular: El tiempo en que demorara en caer y a velcidad con la que llega al suelo
Answer:
1. t = 4.24 s
2. [tex]v_{f} = 42.43 m/s [/tex]
Explanation:
Podemos encontrar el tiempo de caída con la siguiente ecuación:
[tex] v_{f} = v_{0} + gt [/tex] (1)
En donde:
[tex] v_{f}[/tex]: es la velocidad final de la pelota
[tex] v_{0}[/tex]: es la velocidad inicial = 0 (se deja caer)
g: es la aceleración debida a la gravedad = 10 m/s²
Debemos hallar primero la velocidad final. Podemos usar la ecuación:
[tex] v_{f}^{2} = v_{0}^{2} + 2gh [/tex] (2)
En donde:
h: es la altura = 90 m
[tex] v_{f} = \sqrt{2gh} = \sqrt{2*10 m/s^{2}*90 m} = 42.43 m/s [/tex]
Entonces, la velocidad con la que la pelota llega al suelo es 42.43 m/s.
Ahora podemos encontar el tiempo que tarda en caer la pelota resolviendo la ecuación (1) para "t":
[tex] t = \frac{v_{f}}{g} = \frac{42.43 m/s}{10 m/s^{2}} = 4.24 s [/tex]
Por lo tanto, la pelota tarda 4.24 segundos en caer.
Espero que te sea de utilidad!
Why does it take more force to move a heavy box up a ramp than to move the same box down the ramp?
A.There is more friction on the bottom of the box when going up a ramp.
B.Gravity is pushing the box up the ramp at the same time you are pushing the box up the ramp.
C.When you push an object up a ramp, you are working against atmospheric pressure, which is pushing down.
D.When you push an object up a ramp, you are working against gravity, which pulls the box downward.
Find the equivalent resistance of this
circuit.
Ri
R2
1002
2002
R3
600 12
Answer:
63016
Explanation:
Ri+R2+R3 this is called series circuit
Answer:
200
Explanation:
100+200=300
1/300+1/600=200
The elements neon and argon are not reactive
what factors could enhance memory and kept constant? and why
To help make sure information goes from short-term memory to long-term memory, you can use memory-enhancing strategies. One strategy is rehearsal, or the conscious repetition of information to be remembered. Think about how you learned your multiplication tables as a child.
Proven ways to protect memory include following a healthy diet, exercising regularly, not smoking, and keeping blood pressure, cholesterol, and blood sugar in check. Living a mentally active life is important, too. Just as muscles grow stronger with use, mental exercise helps keep mental skills and memory in tone.
According to one study, mental stimulation like reading can help protect memory and thinking skills, especially as you age. The authors even suggest that reading every day can slow down the late-life cognitive decline. ... The act of reading helps to heighten overall brain function and increase memory.
Let's take a deeper dive into evidence-based exercises that offer the best brain-boosting benefits.
Have fun with a jigsaw puzzle. ...
Try your hand at cards. ...
Build your vocabulary. ...
Dance your heart out. ...
Use all your senses. ...
Learn a new skill. ...
Teach a new skill to someone else. ...
Listen to or play music.
The equation below is used to calculate the mechanical advantage of an ideal wheel and axle.
mechanical advantage =
wheel radius
__________
axle radius
A student compares two wheel-and-axle simple machines. Machine 1 has a wheel radius of 50 centimeters, and an axle radius of 10 centimeters. Machine 2 has a wheel radius of 100 centimeters, and an axle radius of 10 centimeters. What is true of these simple machines’ mechanical advantage?
A.
Machine 1’s mechanical advantage is greater, which means that this machine can do more work with less force than Machine 2.
B.
Machine 1’s mechanical advantage is greater, which means that this machine can move faster than Machine 2.
C.
Machine 2’s mechanical advantage is greater, which means that this machine can do more work with less force than Machine 1.
D.
Machine 2’s mechanical advantage is greater, which means that this machine can move faster than Machine 1.
Answer:
b
Explanation:
Machine 2’s mechanical advantage is greater, which means that this machine can do more work with less force than Machine 1.
Mechanical advantageThe term mechanical advantage is the ratio of the radius of wheel to the radius of the axle for a wheel and axle system.
The true statement about the two machines that were compared; 1 and 2 is that, machine 2’s mechanical advantage is greater, which means that this machine can do more work with less force than Machine 1.
Learn more about mechanical advantage:https://brainly.com/question/16617083
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Question 4
The diagram represents the motion of a sound wave. The distance between points A and C is 9 meters (m), and it initially takes the wave 3 seconds (s) to travel.
What will be the wavelength of the sound wave if the velocity of the wave remains constant but the pitch is tripled?
A 3 meters
B 6 meters
с 9 meters
D 18 meters
Answer:A
Explanation:
The wavelength of the sound wave will be 3 meters.
What is wavelength?
The wavelength of any wave is defined as the distance between two max adjacent amplitudes, or the distance between two successive troughs or crest.
Now it is given that:
Distance =9 meters
time = 3 seconds
pitch=1/3 seconds
The velocity of the sound will be
[tex]V=\dfrac{d}{t}=\dfrac{9}{3}=3\ \frac{m}{s}[/tex]
Now from the question the wavelength of the sound wave if the velocity of the wave remains constant but the pitch is tripled
so [tex]f=3\times \dfrac{1}{3}=1 herts[/tex]
Now the velocity of the sound will be
[tex]v=f\times \lambda[/tex]
[tex]\lambda=\dfrac{v}{f}=\dfrac{3}{1}=3\ m[/tex]
Thus the wavelength of the sound wave will be 3 meters.
To know more about wavelength, follow
https://brainly.com/question/10728818
A 100kg linebacker runs with a velocity of 5m/s towards an 88kg quarterback, who begins to back up
with a velocity of 2m/s to avoid being sacked
a.What is the momentum of the linebacker-quarterback system?
b.the quarterback is unsuccessful in evading the linebacker and gets sacked. what is the velocity of the football players just after the linebacker dives in for a tackle if the 2 players move as one clump?
The table below shows the speed of sound waves from musical sound sources at 20°C. Which conclusion can be made based on the information in the table? Wave speed and wavelengths can vary inversely to produce the same frequency. Frequency and wave speed can vary directly to produce the same wavelength. Wavelengths and frequency can vary inversely to produce the same wave speed. Frequency and wavelengths can vary directly to produce the same wave speed. Mark this and return
Answer:
c
Explanation:
Answer:
C
Explanation:
Took it on edg
You are standing on a sheet of ice that covers the football stadium parking lot in Buffalo; there is negligible friction between your feet and the ice. A friend throws you a 0.400-kg ball that is traveling horizontally at 10.0 m/s. Your mass is 70.0 kg. (a) If you catch the ball, with what speed do you and the ball move after ward
Answer:
0.38m/s
Explanation:
Given data
M1= 0.4kg
U1= 10m/s
M2= 70kg
U2= 0m/s
The system experiences an inelastic collision, the expression for inelastic collision is
M1U1+ M2U1= (M1+M2)V
Subsitute
0.4*10+ 70*0= (0.4+10)*V
4= 10.4V
4=10.4V
V= 4/10.4
V=0.38m/s
Hence the common velocity is 0.38m/s
Calculate the distance between a 3.0 x 10^-5 charge and a 2.0 x 10^-6 2 points
C charge if the force between them is 1000 N.
Answer:
thanks for answer:)
Explanation:
a car has a mass of 200kg. It is on a hill 1000m high. How much gravitational potential energy does the car have?
Answer:
Explanation:
PE = m * g * h
m = 200 kg
h = 1000 m
g = 9.81
PE = 200 * 9.81 * 1000
PE = 1962000 Joules
What is the potential difference across a circuit that delivers 4.2A to a 500W motor?
Answer:
Thus, the potential difference is 119 V.
Explanation:
Current, I = 4.2 A
Power, P = 500 W
The rate of doing work is called power.
The SI unit of power is Watt.
The commercial unit of power is horse power.
1 horse power = 746 Watt
The formula of the electrical power is
P = V I
where, V is the voltage and I is the current.
Substitute the values in the formula
500 = 4.2 x V
V = 119 V
Researchers have found that the larvae of all North American firefly species glow as a warning sign to ward off predators. However, the presence and use of lighting organs in adult fireflies vary greatly. Some species use glowing or light flashes as mating signals, while other species produce pheromones as mating signals and do not glow at all. Discuss how the physical characteristics and mating behavior of North American fireflies support the theory of speciation. In your discussion, provide a hypothesis to explain the driving force behind the differences in mating signals among the species.
Explanation:
The theory of speciation confirms what happens with fireflies, only fireflies that are part of the same species can reproduce among themselves, which means that fireflies that use pheromones as mating signals will attract fireflies that use that same form or mechanism of reproduction.
Some mechanisms that allow this type of differentiation or speciation to occur are: seasonal or geographic isolation and sexual isolation due to behavior or conduct.
Speciation allows the formation of new populations of organisms that share the same physiological and genetic characteristics. Therefore, the adult fireflies that shine as a mating signal are possibly found in the same geographical position and their physiological and genetic characteristics are compatible with those of his own species.
What is quantum, in your own words but be more detailed.
Answer: Quantum is really just an amount of any physical entity involved in an interaction.
Explanation:
Why is diffraction used in soil profiles?
Answer:X-ray diffraction (XRD) is the technique most heavily relied on in soil mineralogical analysis. X-ray diffraction is a technique that provides detailed information about the atomic structure of crystalline substances. It is a powerful tool in the identification of minerals in rocks and soils.
Explanation:
XRD is used to identify the minerals composing clay-rich, hydrothermally altered rocks that occur on several Cascade volcanoes. Such rocks are believed to play an important role in the generation of large landslides and mudflows. XRD is used to analyze saline minerals, including borates.
What is the law of conservation of energy?
a
Energy can be changed from one form to another
form but cannot be created nor destroyed.
b An object at rest tends to stay at rest.
C
The right answer is not given.
The change in energy is equal to the
d amount of heat added plus the amount of
work done
Answer:
The answer is A
a crane lifts a 450kg concrete to the top of a 50m building in 5s.assuming g=10m/s²,calculate a,the potential energy if the concrete
Answer:
The answer is 225,000Joules
ASAP!!!!!! I need help is my final
Answer:
bro the answer would be 15m/s north
Explanation:
;)
How come we can see orange? In simple words.
Answer:
When sunlight shines through an orange solution, the violet, blue and green wavelengths are absorbed. The other colors pass through.