Answer:
Correct option: C -> 7.4 kcal
Explanation:
First we need to find the energy necessary to heat the silver from 20°C to 961°. The change in temperature is 961 - 20 = 941, so the energy necessary is:
941 * 0.056 * 100 = 5269.6 cal
Then, for the melting process, we will need:
21 * 100 = 2100 cal
So the total energy needed is:
5269.6 + 2100 = 7369.6 cal = 7.4 kcal
Correct option: C
An ice skater spins at 2.5 rev/s when his arms are extended. He draws his arms in and spins at 10.0 rev/s. By what factor does his moment of inertia change in the process?
Answer:
The moment of inertia decreased by a factor of 4
Explanation:
Given;
initial angular velocity of the ice skater, ω₁ = 2.5 rev/s
final angular velocity of the ice skater, ω₂ = 10.0 rev/s
During this process we assume that angular momentum is conserved;
I₁ω₁ = I₂ω₂
Where;
I₁ is the initial moment of inertia
I₂ is the final moment of inertia
[tex]I_2 = \frac{I_1 \omega_1}{\omega_2} = \frac{I_1*2.5}{10} \\\\I_2 = 0.25I_1 = \frac{1}{4}I_1[/tex]
Therefore, the moment of inertia decreased by a factor of 4
. How does the intensity of sunlight received affect Earth’s temperatures?
Which of the following are two factors that determine speed?
a. acceleration and time
b. distance and time
c. velocity and time
d. motion and time
Answer:
B) Distance and Time
Explanation:
Equation for speed: S = D / T
Speed equals the distance you traveled divided by the amount of time it took to get to that destination.
The two factors which are required to determine the speed of a object are distance traveled by it and time taken by it.
What is speed?The speed is the rate at which the total distance by a object is traveled in the time taken.
Speed of a object can be given as,
[tex]s=\dfrac{d}{t}[/tex]
Here, (d) is the distance traveled by the object and (t) is time taken but the object to cover that distance.
As the unit of the distance is measured in the meter and the time measure in the second. Thus the speed of a object is measured in the meter per second.
In the vehicles the speed of vehicle is also measured in the kilometre per hour or miles per hour.
Hence, the two factors which are required to determine the speed of a object are distance traveled by it and time taken by it.
Thus the option B is the correct option.
Learn more about the speed here;
https://brainly.com/question/359790
The passage helps the reader to draw conclusions about which character's perspective? ºAlec ºAlice ºAlec's father ºAlec's mother
Answer:
I think it might be A: Alec but tell me if I'm wrong
Explanation:
Answer:
a
Explanation:
i did it on e d g e n u i t y
Which structure connects muscles to bone?
Answer: tendons connect muscles to bones
Explanation:
Two water waves meet at the same point, one having a displacement above equilibrium of 60 cm and the other having a displacement above equilibrium of 80 cm.
Answer:
The resultant displacement is 140 cm
Explanation:
say first displacement d₁ is 60 cm
and second displacement d₂ is 80 cm
Resultant displacement = d₁ + d₂
= 60 + 80
= 140 cm
Answer:
Explanation:
To solve this problem it will be necessary to apply the interference principle.
Under this principle interference is understood as a phenomenon in which two or more waves overlap to form a resulting wave of greater, lesser or equal amplitude. In this case, if both are at the same point, the result of the total displacement will be the sum of the individual displacements, therefore
[tex]x = \sum h_i\\\\x = 60cm + 80cm\\\\x =140cm[/tex]
Therefore the resulting displacement above equilibrium is 140cmWhat is the formula for velocity???
Explanation:
divide the distance by the time it takes to travel that same distance, then add your direction to it.
Or change in displacement divided by change in time.
Are carbon compounds rigid and strong
El dibujo muestra donde se encuentra un caracol en distintos instantes de tiempo.?Podemos afirmar que se trata de un movimiento acelerado?Razona tu respuesta
Answer:
if the acceleration is zero the displacements are equal in the same time interval, so we would see the points equally spaced in the diagram
if the acceleration is different from zero in these cases the intervals are different in the same time intervals
Explanation:
In a drawing of displacement as a function of time, we can know if in motion it is steely or not, the relationship that describes the motion is
x = v₀ t + ½ a t²
we see that we have two cases:
* if the acceleration is zero the displacements are equal in the same time interval, so we would see the points equally spaced in the diagram
* if the acceleration is different from zero in these cases the intervals are different in the same time intervals. In the case of positive acceleration the points are spaced and in the chaos negative acceleration the points are getting closer to each other
Un semáforo de 80N cuelga del punto medio de un cable de 30m tendido entre 2 postes. Halle la tensión en cada segmento del cable si éste tiene un pandeo que lo hace descender una distancia vertical de 1m
Answer:
T1 = T2 = 602.33 N
Explanation:
I attached an image of the forces diagram below.
The x component of the forces for this cases is:
[tex]\Sigma F_x=T_1cos\theta-T_2cos\theta=0\\\\T_1cos\theta=T_2cos\theta\\\\T_1=T_2[/tex]
And the y components:
[tex]\Sigma F_y=T_1sin\theta+T_2sin\theta-W=0\\\\T_1=T_2=T\\\\\Sigma F_y=2Tsin\theta=W\\\\T=\frac{W}{2sin\theta}[/tex]
The angle is calculated by using the information about the length of the cable and the vertical distance of the traffic light:
[tex]\theta=tan^{-1}(\frac{1}{15})=3.81\°[/tex]
Thus, you obtain:
[tex]T=\frac{80N}{2(sin3.81\°)}=601.33N[/tex]
hence, the tension in both segments of the cable is 602.33 N
Jenny and Fred both play a long note on their trombones. A stationary observer hears the sound increasing and decreasing repeatedly in loudness. Which of these must be true?
A.The sound waves from the two trombones have slightly different frequencies.
B. The sound waves from the two trombones have the same frequency.
C. The sound waves from the two trombones have slightly different amplitudes.
D. The sound waves from the two trombones have the same wavelength.
E. The sound waves from the two trombones have slightly different velocities.
Answer:
A.The sound waves from the two trombones have slightly different frequencies.
Explanation:
This is because, a difference in frequency of waves from two different sources would result in either constructive or destructive interference of the waves. Thereby, causing the observer to hear the sound increasing or decreasing.
Answer:
A.The sound waves from the two trombones have slightly different frequencies.
I’m a freshman, I got a 80% in the first quarter, 85% in the second and 70% in the third. I have a 46% in the fourth and 34 total absences in the class. If I fail, will I fail the class or the entire grade
Answer:
you will pass but if your grade become lower and u get more absences you will fail
En la etiqueta de un bote de fabada de 350 g, leemos que su aporte energético es de 1630 kj por cada 100 g de producto a) La cantidad de fabada que tiene que comer un hombre si su necesidad energética diaria es 2500 kj para sobrevivir b) El aporte calórico del bote de fabada en calorías
Answer:
(a) 153.37 g
(b) 5705 kJ
Explanation:
(a) To find the amount of bean needed by a man you first calculate the equivalence in beans to 2500kJ
[tex]2500kJ*\frac{100g}{1630kJ}=153.37\ g[/tex]
Thus, 153.37 g has the energy needed by a man that needs 200kJ per day.
(b) The amount of energy per pot of bean is given by:
[tex]E=350g*\frac{1630kJ}{100g}\\\\E=5705\ kJ[/tex]
Thus, the energy is 5705kJ
A paint brush is dropped from the top of a tall ladder and free falls to the ground. What changes, if any, would be observed of the velocity and the acceleration of the brush as it falls? Pick the two answers. The velocity increases. The velocity decreases. The velocity remains a constant value. The acceleration increases. The acceleration decreases. The acceleration remains a constant value.
Answer:
Explanation:
As the paint brush is dropped from the top of a tall ladder it started free falling
i.e. velocity of brush increases as it falls down due to the acceleration provided by gravity.
We know acceleration due to gravity is the attraction experienced by the object due to earth attraction
Value of acceleration due to gravity is constant i.e. [tex]9.8\ m/s^2[/tex]
Therefore the correct choice is
velocity is increasing and acceleration is constant
In an inelastic collision, which of the following statements is always true?
[A] Kinetic energy is conserved in the collision.
[B] Momentum is conserved in the collision.
[C] After the collision, the objects always merge into one.
[D] The collision takes more that 1 second to complete.
Answer: A
Explanation:
A
What energy transformations take place in Joule's system?
Rafael swings a baseball bat with a force of 25 N. The baseball bat exerts a force of 5 N on the baseball. What is the mechanical advantage of the baseball bat? The mechanical advantage of the baseball bat is
Answer:
0.2
Explanation:
Mechanical Advantage is defined as the ratio of force output with respect to the force input. Thus,
MA = output / input
MA = 5 / 25
MA = 1/5
MA = 0.2
Since this value is less then one. Even though it's tagged a mechanical advantage, in reality it would be mechanical disadvantage.
Therefore, we can say that the mechanical advantage of the baseball bat is 0.2
Answer:
0.2
Explanation:
why are the group 17 elements the most reactive of the nonmetal elements a)they are the biggest elements b)they have the fewest electrons c)they are located on the farthest right side of the periodic table d)they require only one electron to fill their outer energy level
Answer:
I think the answer is D-they require onky one electron to fill their outer energy level.
The ____ is a line drawn at a right angle to a barrier. a. normal c. node b. ray d. wave front
Answer:
a. normal
Explanation:
In the field of physics the normal is a line drawn at a right angle to a barrier. In other words the normal line is the line that is drawn perpendicular (right angle, 90 degrees) to the reflective surface of a mirror, or the particular boundary in which refraction occurs at the point of incidence of a light ray. This can be seen in the picture attached below.
2. A new racecar track is being created, and the owners want the cars to complete 10
miles in 7 laps. What does the diameter of the track have to be to meet their
requirements?
Answer:
0.45 miles
Explanation:
since, car will be running on the edge of track, distance covered in one lap by car will be equal to circumference of track.\
we will use value of pi as 22/7
Circumference for any circular shape is given by [tex]\piD[/tex][tex]\pi D[/tex]
Hence, in one lap [tex]\pi D[/tex] distance will be covered
in 7 laps [tex]7 \pi D[/tex] distance will be covered.
but is given that 7 laps should be equal to 10 miles
so 10 miles will be equal to [tex]7\pi D[/tex]
[tex]7\pi D= 10 \ miles\\=> 7*(22/7)* D= 10 \ miles\\=> 22D = 10 \ miles\\=> D = 10/22 \ miles\\=> D = 0.45 \ miles[/tex]
Thus, diameter of track will be 0.45 miles to meet the requirement.
Which phrases describe all the outer planets’ motion? Select two options.
no rotation
fast rotation
slow revolution
opposite revolution
north to south rotation
Answer:
Fast rotation
Slow revolution
Explanation:
Solar system has 8 planets. 4 inner rocky planets - Mercury, Venus, Earth and Mars and 4 outer gaseous planets - Jupiter, Saturn, Uranus and Neptune. The outer planets have few common features.
They are gaseous. There period of revolution is larger than the inner planets which means that they have slow revolution about the Sun. One day on the outer planets is smaller than the inner planets which means they have fast rotation.
For example, Jupiter has revolves around sun in 11.86 Earth years and rotates about axis in 9.8 Earth hours. Uranus revolves around sun in 84 Earth years and rotates on its axis 17.9 Earth hours.
Answer:
Fast rotation
Slow revolution
Explanation:
did the test
What causes atoms to bond together
?!?
Answer:
electrostatic attraction
Explanation:
Atoms form chemical bonds with other atoms when there's an electrostatic attraction between them. This attraction results from the properties and characteristics of the atoms' outermost electrons, which are known as valence electrons.
Jada’s family pulls into a gas station. Her mother fills up the car’s tank with fuel from a pump. Jada notices this symbol on the pump.
Image shows a pump at a gas station with a symbol of corn on it.
What do you think the symbol indicates?
A. This gasoline is to be used only in farm vehicles.
B. It is not safe to have gasoline around food products.
C. This gasoline can also be used as a fertilizer to help plants grow.
D. A biomass has been used as part of the fuel.
Answer:
D- a biomass has been used as a part of the fuel.
How does the temperature of water affect the speed of the sound waves?
Answer:
Temperature is also a condition that affects the speed of sound. Heat, like sound, is a form of kinetic energy. Molecules at higher temperatures have more energy, thus they can vibrate faster. Since the molecules vibrate faster, sound waves can travel more quickly.
Gold, quartz, and talc are minerals. Copper and iron are types of ore. What is the difference between minerals and ores?
A mineral is a non-living, solid substance that can be extracted from the ground. Ore is a type of mineral made up of metals.
An ore is non-living and solid with little value unless it occurs in large amounts, in which case it is a mineral.
O A mineral is a valuable form of ore that can be extracted from the ground
O A mineral is a non-living, solid substance made of elements. Ore is a large deposit of one or more valuable minerals in the ground.
Answer:
A mineral is a valuable form of ore that can be extracted from the ground
Explanation:
Gold, quartz and talc are minerals because they are found in the earth in a valuable form of ore while ores are rocks that contain valuable concentrations of minerals.that can be mined.
An ORE in general term can be said to be a mineral deposit that contains enough Minerals that can be mined in commercial quantities while Minerals are valuable components of an Ore that can be mined ( naturally occurring ) in an ORE.
How far can you get away from your little brother with a paintball marker if you can travel at 3 m/s and you have 15s before he sees you?
a man is trying to move a piano by himself, but it will not move, what force must they overcome to start the piano moving?
Answer:
The friction of the piano and the weight
Explanation:
An air-track glider attached to a spring oscillates between the 10.0 cm mark and the 61.0 cm mark on the track. The glider completes 11.0 oscillations in 31.0 s
Answer:
T = 2.82 seconds.
The frequency [tex]\mathbf{f = 0.36 \ Hz}[/tex]
Amplitude A = 25.5 cm
The maximum speed of the glider is [tex]\mathbf{v = 56.87 \ rad/s}[/tex]
Explanation:
Given that:
the time taken for 11 oscillations is 31 seconds ;
SO, the time taken for one oscillation is :
[tex]T = \frac{31}{11}[/tex]
T = 2.82 seconds.
The formula for calculating frequency can be expressed as :
[tex]f = \frac{1}{T}[/tex]
[tex]f = \frac{1}{2.82}[/tex]
[tex]\mathbf{f = 0.36 \ Hz}[/tex]
The amplitude is determined by using the formula:
[tex]A = \frac{d}{2}[/tex]
The limits that the spring makes the oscillations are from 10 cm to 61 cm.
The distance of the glider is, d = (61 - 10 )cm = 51 cm
Replacing 51 for d in the above equation
[tex]A = \frac{51}{2}[/tex]
A = 25.5 cm
The maximum speed of the glider is:
[tex]v = A \omega[/tex]
where ;
[tex]\omega = \frac{2 \pi}{T}[/tex]
[tex]\omega = \frac{2 \pi}{2.82}[/tex]
[tex]\omega = 2.23 \ rad/s[/tex]
[tex]v = A \omega[/tex]
[tex]v = 25.5 *2.23[/tex]
[tex]\mathbf{v = 56.87 \ rad/s}[/tex]
The baker needs 9 eggs, 6 cups of flour, 3 cups of sugar, and 3 sticks of butter to make a total of 3 cakes.. The baker only has 2 sticks of butter. That means the butter is the ___________ because the baker can only make 2 cakes!
Question 19 options:
Product
Reactant
Limiting reactant
Spontaneous reactant
Answer: Limiting reactant
Explanation:
The limiting reactant is a reactant will get completely consumed up in the reaction. This reactant being in low concentration will lead to the formation of limited amount of product.
In the given situation, since the butter cakes are required to be 3 sticks for making 3 cakes but only 2 cakes are available thus the butter stick is the limiting reactant.
Which of the following metric system units is used when measuring large quantities of water?
Gallons
Liters
mL
Cup
Answer:
I want to say Liters but not 100% sure
