Answer:
I think C
Explanation:
kinetic energy formula: 1/2mv^2
1/2(620kg)(9m/s)^2
1/2(620kg)(81m/s)
1/2(50220)
KE = 25110 J
What will happen if we increase the friction on a roller coaster?
A. The speed of the roller coaster will increase.
B. The speed of the roller coaster will decrease
C. The speed of the roller coaster will remain constant.
D. The roller coaster will fly away
Answer: B. The speed will decrease.
Explanation:
When you ride a roller coaster, the wheels rub/scrape the rails, creating heat as a result of friction. And friction will slow you down. So increasing the friction on a roller coaster would slow it down.
Answer:
B
Explanation:
Friction opposes motion therefore reducing motion
if 8000cm3 of liquid drains off an hour glass in one hour, what is the flow rate of water from the clock
Answer:
8000cm³/hr
Explanation:
Given parameters:
Volume of the liquid draining off per hour = 8000cm³
Time taken to drain off = 1hr
Unknown:
Flow rate = ?
Solution:
Flow rate is the volume of fluid that passes per unit of time.
Flow rate = [tex]\frac{volume of fluid}{time taken}[/tex]
Flow rate = [tex]\frac{8000cm^{3} }{1hr}[/tex]
Flow rate = 8000cm³/hr
Cellular respiration takes place in the mitochondria of cells.
Answer:
True
Because mitochondria is the powerhouse of the cell.
Explanation:
Hope this helps you
Answer:
True
Explanation:
The diagram below shows the velocity vectors for two cars that are moving relative to each other.
From the frame of reference of car 1, what is the velocity of car 2?
Answer:
The answer is "[tex]5 \ \frac{m}{s} \ west[/tex]"
Explanation:
[tex]\to \vec{V_1} = (25 \frac{m}{s}) (\hat{-i})\\\\\to \vec{V_2} = (20 \frac{m}{s}) (\hat{-i})\\\\[/tex]
velocity of car | respect to car :
[tex]\to \vec{V_{12}} = \vec{V_1} - \vec{V_2}\\\\[/tex]
[tex]=\vec{-25} \hat{i}+ \vec{20} \hat{i}\\\\= 5 \ \frac{m}{s} \ west[/tex]
Answer:
70 m/s east
Explanation:
What is the effect on the current in a simple circuit when both the voltage and the resistance are halved?
Answer:
It doesn't change. It stays the same.
I hopes this helped you and if it did I'm glad I helped someone!!!
Explanation:
How long would it take for someone to bike to school if the school is 10 km away and the
cyclist is riding at 5 km/hr
Answer:
It would take the cyclist 2 hours to cycle to school.
Explanation:
5km/hr for 2 hours would be 10km.
which change to a circuit is most likely to increase it electrical power
A: increase it's current and increase it's voltage
B: decrease it's current and increase it's voltage
C: decrease it's current and decrease it's voltage
D: increase it's current and decrease it's voltage
Answer:
A................
Explanation:
Hope this helps you
A. increase it's current and increase it's voltage
Explanation:
A 7-kg bowling ball moving at 4 m/s strikes a 1 kg bowling pin. If the ball slows to 2 m/s in 0.05 s, how much force does it exert on the pin?
Please, show your work.
Answer:
280 N
Explanation:
acceleration = v2-v1 / time taken = (2-4 )/ 0.05 = -40 m/s^2 ( neg sign indicates slowing down )
force exerted = ma = 7 kg x -40 m/s^2 = - 280 N ( neg sign means opposite direction of initial velocity )
since the 7 kg ball is slowing down, the direction of force will be opposite of the initial velocity , and it will be 280 N
A battery and a resistor are wired into a circuit. The resistor dissipates 0.30 W. Now two batteries, each identical to the original one, are connected in series with the resistor. What power does it dissipate?
Answer:
1.2 W
Explanation:
Let the value of resistance be R , emf of battery be E
current i = E / R
power = i² R
= E² x R / R²
= E² / R
Given
E² / R = .30
when two batteries are connected
Total emf = 2E
current = 2E / R
Power = ( 2E / R )² x R
= 4 E² / R
= 4 x .30
= 1.2 W .
A car accelerates from 20 m/s to 80 m/s in 5 seconds. What is the
average acceleration of the car?
a 20 m/s2
b 12 m/s2
C 4 m/
d 16 m/s2
Answer:
12m/s2
Explanation:
:D (just a smiley, not answer d)
What is a super dense gravitationally collapsed mass from which no light
can escape called?
1) neutron star
2) pulsar
3) supernova
4) black hole
A robot probe drops a camera off the rim of a 239 m high cliff on Mars, where the free-fall acceleration is -3.7 m/s^2. Find the velocity with which the camera hits the ground.
Answer:
42.05 m/s
Explanation:
From the question given above, the following data were obtained:
Initial velocity (u) = 0 m/s
Height (h) = 239 m
Acceleration due to gravity (g) = 3.7 m/s²
Final velocity (v) =?
The velocity with which the camera hits the ground can be obtained as follow:
v² = u² + 2gh
v² = 0² + 2 × 3.7 × 239
v² = 0 + 1768.6
v² = 1768.6
Take the square root of both side
v = √(1768.6)
v = 42.05 m/s
Therefore, the velocity with which the camera hits the ground is 42.05 m/s
Se lanza una pelota y regresa al punto de partida 2.5 s después ¿Que altura máxima alcanzara? ¿a que altura se hallaba 1 segundo después del lanzamiento?
Answer:
a) [tex] y_{max} = 7.7 m [/tex]
b) y = 7.4 m
Explanation:
a) La altura máxima que alcanza la pelota se puede encontrar usando la siguiente ecuación:
[tex] y_{max} = y_{0} + v_{0y}t - \frac{1}{2}gt^{2} [/tex] (1)
En donde:
[tex]y_{0}[/tex]: es la altura inicial = 0
[tex]v_{0y}[/tex]: es la velocidad inicial en y
g: es la gravedad = 9.81 m/s²
t: es el tiempo
Primero debemos encontrar la velocidad inicial en y:
[tex] v_{fy} = v_{0y} - gt [/tex]
Sabiendo que la velocidad final en y es igual a cero (en la altura máxima), y con t = 1.25 s (la mitad del tiempo total) tenemos:
[tex] v_{0y} = gt = 9.81 m/s^{2}*1.25 s = 12.3 m/s [/tex]
Ahora, podemos encontrar la altura máxima:
[tex] y_{max} = v_{0y}t - \frac{1}{2}gt^{2} = 12.3 m/s*1.25 s - \frac{1}{2}9.81 m/s^{2}*(1.25 s)^{2} = 7.7 m [/tex]
b) Podemos encontrar la altura cuando t = 1 s con la misma ecuación (1):
[tex]y_{max} = y_{0} + v_{0y}t - \frac{1}{2}gt^{2} = 12.3 m/s*1 s - \frac{1}{2}9.81 m/s^{2}*(1 s)^{2} = 7.4 m[/tex]
Por lo tanto, la pelota se encontraba a 7.4 m luego de 1 segundo despúes del lanzamiento.
Espero que te sea de utilidad!
what are some advantages of gravitational energy
Answer:
Explanation: Gravity keeps our bones and bodily muscles from not working, things like dams can be one example of gravitational energy being used for our benefits. Without gravitational energy, our earth most likely won't stay in it's own atmosphere. Another example is like a car on the top of the hill, or a snow pack (Where an avalanche might happen)
6. A total of 135 J of work is done on a gaseous refrigerant as it undergoes compression. If
the internal energy of the gas increases by 114 J during the process, what is the total amount
of energy transferred as heat? Has energy been added to or removed from the refrigerant as
heat?
Answer:
Eh = 21 [J]
Removed as heat.
Explanation:
This is a case of energy conservation, we have to take into account the energies that go in and out of the system. In this case, 135 [J] of energy are entered in the form of work of the compressor to the chamber where the refrigerant is compressed, now of these 135 [J] 114 [J] were used as internal energy, this internal energy is used to increase the pressure and temperature of the refrigerant.
In this way the rest of the energy of the 135 [J] was lost in the form of heat to determine this loss of energy, we simply perform the arithmetic subtraction.
Eh = 135 - 114 = 21 [J]
Eh = 21 [J]
An object with an initial speed of 4.0 m/s accelerates uniformly at 2.0 m/s^2
in the direction of its motion for a distance of 5.0 meters. What is the final
speed of the object?
What, exactly, is moving across the medium?
Answer:
So waves are everywhere. But what makes a wave a wave? What characteristics, properties, or behaviors are shared by the phenomena that we typically characterize as being a wave? How can waves be described in a manner that allows us to understand their basic nature and qualities?
A wave can be described as a disturbance that travels through a medium from one location to another location. Consider a slinky wave as an example of a wave. When the slinky is stretched from end to end and is held at rest, it assumes a natural position known as the equilibrium or rest position. The coils of the slinky naturally assume this position, spaced equally far apart. To introduce a wave into the slinky, the first particle is displaced or moved from its equilibrium or rest position. The particle might be moved upwards or downwards, forwards or backwards; but once moved, it is returned to its original equilibrium or rest position. The act of moving the first coil of the slinky in a given direction and then returning it to its equilibrium position creates a disturbance in the slinky. We can then observe this disturbance moving through the slinky from one end to the other. If the first coil of the slinky is given a single back-and-forth vibration, then we call the observed motion of the disturbance through the slinky a slinky pulse. A pulse is a single disturbance moving through a medium from one location to another location. However, if the first coil of the slinky is continuously and periodically vibrated in a back-and-forth manner, we would observe a repeating disturbance moving within the slinky that endures over some prolonged period of time. The repeating and periodic disturbance that moves through a medium from one location to another is referred to as a wave.
Hope That Helps!!
Explanation:
For a straight line on a position-time graph, the slope of the line represents:
Group of answer choices
velocity
displacement
acceleration
distance
Why do we use insulators if they prevent the flow of electricity?
Answer:
letterman is shooting the kids
We use insulators to avoid being electrocuted. electricians use rubber gloves to avoid shock. Cables are insolated with rubber so you can hold them without getting shocked even if it is plugged in.
10. A boat traveling at 9.5 m/s reduces its acceleration at a rate of 2.5 m/s2. What is the final speed of the boat
after it travels 12 meters?
Answer:
6.75m/s
Explanation:
using the second equation of motion, the time is calculated.
and with the formula a= (v - u)/t
where a is acceleration but in this case it's deceleration (and should be negated as you solve it ) .
v is final velocity
u is initial velocity
t is time taken
A student is doing a genetics experiment on beetles. The student breeds a pure green beetle with a pure brown beetle. The student repeats this experiment ten more times. Every time the student performs this cross, all of the offspring are green. What does that mean? A. The gene for green and brown are equally expressed because half the beetle parents have a green phenotype and half the beetle parents have a brown phenotype. B. The gene for green color is dominant over the gene for brown because all the beetle offspring have a brown phenotype. C. The gene for brown color is dominant over the gene for green color because all of the beetle offspring have a brown genotype. D. The gene for green color is dominant over the gene for brown color because all the beetle offspring have a green phenotype.
Answer:
b
Explanation:
bbhbh
The genes for green color are dominant over the genes for brown color because all the beetle offspring have a green phenotype. Therefore, option (D) is correct.
What is phenotype?In biology, a phenotype can be described as the observable characteristics of an organism which is the result of the interaction of environmental factors and genes. These traits involve physical appearances and any traits that we can observe.
The phenotype includes its physiological, biochemical, as well as behavioral properties. Genotype is inherited from the parents while the phenotype can be affected by lifestyle and environmental factors. Environmental factors such as nutrition, temperature, humidity, and mental health of the organism.
For example, flamingoes are white in color but turn pink because of the pigments they need from their diet. Therefore, flamingoes portray how they are affected by environmental factors. The phenotype of an organism changes, accordingly to environmental factors.
Learn more about phenotype, here:
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state the law of conservation of energy
Answer:
In physics and chemistry, the law of conservation of energy states that the total energy of an isolated system remains constant; it is said to be conserved over time. ... For instance, chemical energy is converted to kinetic energy when a stick of dynamite explodes.
List and describe the 5 health reaped components of fitness.
Answer:
(1) body composition, (2) flexibility, (3) muscular strength, (4) muscular endurance, and (5) cardiorespiratory endurance.
Momentum is a product of mass and....?
Answer:
Momentum is a product of mass and velocity.
Explanation:
Hope this helps you
Crown me as brainliest:)
Describe Kinetic Energy.
In which image below is the angle of refraction the greatest?
Answer:
Explanation:
Angle of refraction is the angle made by refracted ray with the normal at the point of incidence . In this figure , refracted ray has been shown by line having arrow-head . Normal has been shown by broken line .
We observe that in figure D , angle made by refracted ray with normal is greatest . So figure D is the answer.
The image where the angle of refraction is the greatest is the image D
What is the angle of refraction?The angle of refraction is the angle that the refracted ray made with the x-axis.
The higher the angle between the refracted ray and the x-axis, the higher the angle of refraction and vice versa.
From the given diagram, we can see that the image where the angle of refraction is the greatest is the image D
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1.A runner has a displacement of 20 meters in 5 seconds, what is his velocity
during this time?
Answer:
The required velocity of runner is 4m/s.
What is the difference between physical & chemical changes?
Slate whether each is an example of a Physleat (P) or Chemteal (C) property
1. Arock's density
2. boiling point of Gatorade
3. ability of an old car to rust
4. red color of a pe apple
S ability of wood to ignite
8. bitler taste of a lemon
7. melting point of wax
8. hardness of marble
9. Luster (shininess) of gold
boiling point Gatoride
If the density of water is 1000 kg/m², what is the pressure at the bottom of a swimming pool 2m
deep when it is full of water?
The pressure at the bottom when the given tank is full of water will be 19600 Pa.
Pressure can be calculated by the formula,
[tex]\bold {P = \rho h g}[/tex]
Where,
P- pressure = ?
[tex]\bold {\rho}[/tex] - density of water = 1000 kg/m²
h - height of water = 2 m
g - gravity acceleration = 9.8 m/s
Put the values in the formula
[tex]\bold {P = 2 \times 1000 \times 9.8} \\\\\bold {P = 19600\ Pa}[/tex]
Therefore, the pressure at the bottom when the given tank is full of water will be 19600 Pa.
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An object originally moving at a speed of 20. meters per second accelerates uniformly for 5.0 seconds to a
final speed of 50. meters per second. What is the acceleration of the object?
Answer:
92
Explanation: