Two ice-skaters are skating in circles on a frozen pond. Maria is making large circles with a radius of 12 m and skating 4.5 m/s. Her friend, Samantha, is making smaller circles with a radius of 6 m but is not skating as quickly, going only 3.8 m/s.
How could each skater increase her centripetal acceleration without changing the size of her path? Explain your reasoning.
Answer: Samantha has the largest centripetal acceleration of 2.4 m/s^2. Maria has only 1.69 m/s^2.
Explanation:
Earthquakes
Shaking of the ground
Seismographs
Scientific method
Answer:
C. seismographs
Explanation:
Theirs another name for seismographs but c is correct
How much heat in kcal is required to change 0.5 kg of ice, originally at - 10 0 * C into steam at 110 C?Constants needed in the problemLatent heat of fusion=79.7 kcal/kg Specific heat of ice=0.5 kcal/kg/K ; Latent heat of vaporization ation = 539 kcal/kg ; Specific heat of water 1.0 kcal/kg/K Specific heat of ieam=0.480 kcal/kg
Answer:
Q = 364.25 kcal
Explanation:
In this question, we will have to calculate the heat absorptions for different steps of temperature rise and phase change. And then we will ad them to calculate total heat absorbed.
1. RISE IN TEMPERATURE OF ICE:
First, the temperature of ice will be increased from - 10°C to 0 °C. Heat absorbed during this process will be given as:
Q₁ = mC₁ΔT₁
where,
Q₁ = Heat absorbed while increasing temperature of ice = ?
m = mass of ice = 0.5 kg
C₁ = specific heat of ice = 0.5 kcal/kg k
ΔT₁ = change in temperature of ice = 0 - (-10) = 10 k
Therefore,
Q₁ = (0.5 kg)(0.5 kcal/kg.k)(10)
Q₁ = 2.5 kcal
2. MELTING OF ICE:
Now, the melting of ice will occur at 0°C and the heat absorbed during this process will be:
Q₂ = m(Latent Heat of Fusion of Ice)
where,
Q₂ = heat Absorbed during melting of ice = ?
Therefore,
Q₂ = (0.5 kg)(79.7 kcal/kg)
Q₂ = 39.85 kcal
3. RISE IN TEMPERATURE OF WATER:
Now, the temperature of water will be increased from 0°C to 100 °C. Heat absorbed during this process will be given as:
Q₃ = mC₃ΔT₃
where,
Q₃ = Heat absorbed while increasing temperature of water = ?
m = mass of water = 0.5 kg
C₃ = specific heat of water = 1 kcal/kg k
ΔT₃ = change in temperature of ice = 100 - 0 = 100 k
Therefore,
Q₃ = (0.5 kg)(1 kcal/kg.k)(100 k)
Q₃ = 50 kcal
4. VAPORIZATION OF WATER:
Now, the vaporization of water will occur at 100°C and the heat absorbed during this process will be:
Q₄ = m(Latent Heat of Vaporization of Water)
where,
Q₄ = heat Absorbed during vaporization of water = ?
Therefore,
Q₄ = (0.5 kg)(539 kcal/kg)
Q₄ = 269.5 kcal
5. RISE IN TEMPERATURE OF STEAM:
Now, the temperature of steam will be increased from 100°C to 110 °C. Heat absorbed during this process will be given as:
Q₅ = mC₅ΔT₅
where,
Q₅ = Heat absorbed while increasing temperature of steam = ?
m = mass of steam = 0.5 kg
C₅ = specific heat of steam = 0.48 kcal/kg k
ΔT₅ = change in temperature of ice = 110 - 100 = 10 k
Therefore,
Q₅ = (0.5 kg)(0.48 kcal/kg.k)(10 k)
Q₅ = 2.4 kcal
Hence, the total heat absorbed to change 0.5 kg of ice at - 10°C into steam at 110°C will be:
Q = Q₁ + Q₂ + Q₃ + Q₄ + Q₅
Q = 2.5 kcal + 39.85 kcal + 50 kcal + 269.5 kcal + 2.4 kcal
Q = 364.25 kcal
4) Choose Yes or No next to the descriptions to indicate whether or not an object
is accelerating,
A car slows down,
A car stays the same speed,
A car goes faster,
Luke walks at a constant speed of 4 mph,
Luke walks north at a constant speed of 4 mph,
Luke walks north at a constant speed of 4 mph, turns right, and walks
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if the volume of a cube is 100cm3. what's the measurement of one of its length
Answer:
100 cm
Explanation:
Answer:
4.64
Explanation:
The cube root of 100 is 4.64.
A 615.00 kg race car is uniformly traveling around a circular race track. It takes the race car 20.00 seconds to do one lap around the 80.00 m radius circular track. What is the frequency of the race car's circular motion?
Answer:
The value is [tex]f = 0.05 \ Hz[/tex]
Explanation:
From the question we are told that
The mass of the car is [tex]m = 615 \ kg[/tex]
The period of the circular motion is [tex]T = 20 \ s[/tex]
The radius is [tex]r = 80 \ m/s[/tex]
Generally the frequency of the circular motion is
[tex]f = \frac{1}{T }[/tex]
=> [tex]f = \frac{1}{ 20 }[/tex]
=> [tex]f = 0.05 \ Hz[/tex]
A jet aircraft is traveling at 214 m/s in hor-
izontal flight. The engine takes in air at a
rate of 115 kg/s and burns fuel at a rate of
2.53 kg/s. The exhaust gases are ejected at
276 m/s relative to the aircraft.
Find the thrust of the jet engine.
Answer in units of N.
Answer:
The thrust is [tex]F = 7828.3 \ N [/tex]
Explanation:
From the question we are told that
The speed of the jet aircraft is [tex]v = 214 \ m/s[/tex]
The rate at which the engine takes in air is [tex]\^ Q = 115 \ kg/s[/tex]
The rate at which the engine burns fuel is [tex]\r m = 2.53 \ kg/s[/tex]
The speed of the exhaust gases is [tex]u = 276 \ m/s[/tex]
Generally the thrust of the engine is mathematically represented as
[tex]F =[ \^ Q * ( u - v )] + (\r m * u)[/tex]
=> [tex]F =[ 115 * ( 276 - 214 )] + (2.53 * 276)[/tex]
=> [tex]F = 7828.3 \ N [/tex]
What types of energy is used to make a lamp work
Answer:
Electrical energy
Explanation:
How much power is used if a force of 35 newtons is used to push a box a distance of 10 meters in 5 seconds?w=350j
Answer:
How much power is used if 350J of work is done when pushing a box for 5 seconds.
Explanation:
the answer is 70watts
A 3900 kg truck is moving at 6.0 m/s what is the kinetic energy
Answer:
70200J
Explanation:
k.E = 1/2mv^2
K.E = 1/2(3900)(6)^2
Suppose you are in a moving car and the motor stops running. You step on the brakes and slow the car to half speed. If you release your foot from the brakes, will the car speed up a bit, or will it continue at half speed and slow due to friction?
Answer:
See the answer below
Explanation:
If you step on the brake of a car while driving, the frictional force between the tires of the car and the surface of the road increases in opposition to the motion of the car. Consequently, the car slows down.
If you release your foot from the brake pedal when the car is still at half speed, the frictional force reduces and the car speeds up a bit even without pressing the throttle. Eventually, the frictional force will slow down and stop the car if the throttle is not pressed.
A train travels at a speed of 30mph and travelled a distance of 240 miles. How long did it take the train to complete its journey? Must show your work
Answer:
8
Explanation:
240 divided by 30 = 8
A boy is exerting a force of 70 N at a 50-degree angle on a lawnmower. He is accelerating at 1.8 m/s2. Round the answers to the nearest whole number.
What is the mass of the lawnmower?
What is the normal force exerted on the lawnmower?
The lawnmower accelerates in the positive horizontal direction, so that the net horizontal force is, by Newton's second law,
(70 N) cos(-50°) = m (1.8 m/s²)
where m is the mass of the lawnmower. Solve for m :
m = ((70 N) cos(-50°)) / (1.8 m/s²)
m ≈ 25 kg
The lawnmower presumably doesn't get lifted off the ground, so that the net vertical force is 0. If n is the magnitude of the normal force, then by Newton's second law,
n - m g + (70 N) sin(-50°) = 0
n = m g + (70 N) sin(50°)
n = (25 kg) (9.8 m/s²) + (70 N) sin(50°)
n ≈ 300 N
a toy car is wound up and released on the floor. it accelerates at a rate of 0.4 m/s/s . the mass of the care is 3kg. what is the force that the cars wheels exert on the floor.
Answer:
1.2N
Explanation:
f=m×a
m=3kg
a=.4m/s/s
3×.4=1.2
kg×m/s/s = N
why is thouching the live wire of an appliane when it is connecfed to the mains dangerous
Answer: The live wire is the most dangerous one, since it is at 230 V. it should never touch the earth wire (unless the insulation is between them, of course!), because this would make a complete circuit from your mains supply to the ground (earth). A shock or fire would be highly likely.
Explanation:
what makes up a atom
Answer:
They're typically made up of three main parts: protons, neutrons and electrons. Think of the protons and neutrons as together forming a “sun”, or nucleus, at the centre of the system. The electrons orbit this nucleus, like planets. If atoms are impossibly small, these subatomic particles are even more so.
Explanation:
hope i helped.
Answer:
Atoms consist of a nucleus made of protons and neutrons orbited by electrons. ... We now know that atoms are made up of three particles: protons, neutrons and electrons — which are composed of even smaller particles, such as quarks.
Explanation:
The weight of an object is measured in air to be 7.0 N. The
object is then immersed in water and its apparent weight is
measured to be 4.0 N. Determine the buoyant force and state
whether or not the object floats.
Answer:
Buoyant force = 3.0 N
The object will not float.
Explanation:
Apparent weight of a body immersed in water is the actual weight of object minus buoyant force
Given in the question that;
Weight of object in air = 7.0 N
Apparent weight of object = 4.0 N
4.0 N = 7.0 N - Buoyant force
Buoyant force = 7.0 - 4.0 = 3.0 N
In this case, the buoyant force is less than weight of the object thus the object will sink.
How do you compare the mass of proton, neutron, and
electron?
Answer:Explanation:
Protons and neutrons have very similar mass, while electrons are far lighter, approximately 11800 times the mass. Protons are positively charged, neutrons have no electric charge, electrons are negatively charged. The size of the charges is the same, the sign is opposite.
Making and disposing of synthetic materials affects the amount of natural resources that are available. It also can harm the environment. These problems may not affect us in our lifetime. Who will these problems affect?
Answer:
What I put- This will affect animals, the earth, and could affect future generations. Plastic also gets into the oceans causing sea creaters die by eating it.
Sample Answer- Problems that arise from the unavailability of natural resources and from environmental hazards will affect the generations that follow us.
Explanation:
Answer:
This will affect animals, the earth, and could affect future generations. Plastic also gets into the oceans causing sea creaters die by eating it.
Explanation:
A 0.85-kg arrow flies through the air at a speed of 19 m/s. What is the momentum of the arrow?
16 kg m/s
22 kg m/s
160 kg m/s
360 kg m/s
Answer:
16 kg m/sExplanation:
The momentum of an object can be found by using the formula
momentum = mass × velocity
From the question we have
momentum = 0.85 × 19 = 16.15
We have the final answer as
16 kg m/sHope this helps you
Please help which one !!
Answer:
4th one
Explanation:
Where are alkaline earth metals found on the periodic table?
Group 1
Group 2
Groups 3–12
Group 17
Answer:
B
Explanation:
Answer:
B
Explanation:
I had a feeling
How much power will it take to move a 10 kg mass at an acceleration of 2 m/s² a distance of 10 meters in 5 seconds?
Answer:
100 Watts
Explanation:
These equations are needed to work out the answer:
power= work done/ time takenwork done= force* distanceforce= mass* accelerationforce: 10 kg* 2m/s= 20
work done: 20* 10m=200
power: 200/2=100
What average net force is required to stop a 1950 kg car in 10.5 s if it’s initially traveling at 28m/s
Answer:
An average net force of 5200 N is needed to stop the car
Explanation:
Cinematics and Dynamics
Cinematics describes the variables involved in the movement without dealing with its causes. There are four main concepts in cinematics: Velocity (or its scalar equivalent, the speed), acceleration, time, and displacement (or the scalar equivalent, distance).
The acceleration can be calculated by:
[tex]\displaystyle a=\frac{v_f-v_o}{t}[/tex]
The initial speed is vo=28 m/s, it stops (vf=0) in t=10.5 seconds, thus the acceleration is:
[tex]\displaystyle a=\frac{0-28}{10.5}[/tex]
[tex]a = -2.67~m/s^2[/tex]
The acceleration is negative because the car loses speed.
Knowing the mass of the car m=1950 Kg, we can calculate the net force required to stop the car by using the formula:
F = m.a =1950*2.67
F = 5200 N
An average net force of 5200 N is needed to stop the car
Los muelles de un remolque están calibrados para soportar su peso, cuando se carga el remolque con 2100 kg, la fuerza ejercida es de 20580 N comprime los muelles de un remolque 5,5 cm a)Longitud que desciende el remolque si se carga con 28000 N b)Si ha descendido 4,2 cm la carga
Answer:
a) El remolque desciende 7.4 cm
b) La carga debe ser de 15715.6 N ó 1603.6 kg
Explanation:
Para los cálculos que involucren muelles, se aplica la Ley de Hooke, la cual relaciona el efecto de una Fuerza y el cambio de longitud que esta ejerce, en un resorte de elasticidad dada.
Escrito en fórmula:
[tex]F=-k \cdot \Delta L[/tex]
Donde:
F es la fuerza ejercida
k es la constante elástica del muelle
ΔL es la variación de longitud del muelle
El problema indica que al cargar 2100 kg se ejerce una fuerza de 20580 N
Esto se corrobora con la 2da ley de Newton y asumiendo una aceleración de gravedad de 9.8 [tex]\frac{m}{s^{2} }[/tex]
[tex]F_{1} =m \cdot a\\F_{1}=2100kg \cdot 9.8\frac{m}{s^2}\\F_{1}=20580N[/tex]
Esta fuerza comprime o reduce la longitud del muelle en 5.5 cm. Usando estos datos en la Ley de Hooke, podemos obtener la constante elástica k:
[tex]F=-k \cdot \Delta L\\20580N=-k \cdot (-0.055m)\\\\k=\frac{20580N}{0.055m}\\k= 374181\frac{N}{m}[/tex]
Ahora ya tenemos los datos para resolver las preguntas:
a) Longitud que desciende el remolque si se carga con 28000 NAplicando directamente la formula de la Ley de Hooke:
[tex]F=-k \cdot \Delta L\\\Delta L=\frac{F}{-k} \\\Delta L= \frac{28000N}{-374181\frac{N}{m}} \\\Delta L=-0.074 m = -7.4cm[/tex]
b) Si ha descendido 4,2 cm la cargaEn este caso debemos calcular la fuerza necesaria que haga descender el remolque 4.2cm. Nuevamente utilizando la Ley de Hooke con estos nuevos datos:
[tex]F=-k \cdot \Delta L\\F=-374181\frac{N}{m} \cdot (-0.042m)\\F=15715.6N[/tex]
Si queremos saber la carga en kilogramos:
[tex]F = m \cdot a\\m = \frac{F}{a} \\m = \frac{15715.6N}{9.8\frac{m}{s^2} }\\m= 1603.6 kg[/tex]
What 2 factors affect the impulse on an object in a collision?
Arrange Kepler's laws in order: a. The ratio of the squares of the periods of any two planets revolving around the sun is equal to the ratio of the cubes of their average distance from the sun. b. The path of each planet around the sun is an ellipse with the sun at one focus. c. As a planet moves in its orbit, a line from the sun to the planet sweeps out equal areas in equal times. a. 3, 2, 1 b. 2, 3, 1 c. 3, 1, 2 d. 1, 2, 3
Answer:
2,3,1
Explanation:
There are 3 laws of Kepler.
First law = The path of each planet around the sun is an ellipse with the sun at one focus.
Second law = As a planet moves in its orbit, a line from the sun to the planet sweeps out equal areas in equal times.
Third law = The ratio of the squares of the periods of any two planets revolving around the sun is equal to the ratio of the cubes of their average distance from the sun.
Hence, the correct order for Kepler's law is: 2,3,1
What type of energy is stored in a pendulum at the top of its arc?
Answer:
potential
Explanation:At this point the energy is stored in a form called potential energy. This means that the system has the potential to do work or to become active thanks here to the weight's position high above the lowest point of its swing.
Whet net force is required to accelerate a car at a rate of 10 m/s2 if the car
has a mass of 5,000 kg?
Answer:
[tex]\boxed {\boxed {\sf 50,000 \ Newtons }}[/tex]
Explanation:
Force can be found by multiplying the mass by the acceleration.
[tex]F=m*a[/tex]
The mass of the car is 5,000 kilograms and it's acceleration is 10 meters per square second.
[tex]m= 5,000 \ kg \\a= 10 \ m/s^2[/tex]
Substitute the values into the formula.
[tex]F= 5,000 \ kg * 10 \ m/s^2[/tex]
Multiply.
[tex]F= 50,000 \ kg*m/s^2[/tex]
1 kilogram meter per square second is equal to 1 Newton. So, our answer of 50,000 kg*m/s² is equal to 50,000 Newtons[tex]F= 50,000 \ N[/tex]
A net force of 50,000 Newtons is required to accelerate a 5,000 kilogram car at 10 meters per square second.
A 1.0 kg ball has a potential energy of 10 J and falls to the ground. What is the velocity right before it hits the ground?
a)20 m/s
b)10 m/s
c)4.5 m/s
d)15 m/s
Answer:
10m/s
Explanation: