Answer:
An object is in notion if its position change with time.
Which option is an example of a pure substance?
A. The compound strontium oxide
B. Carbon atoms spread evenly throughout iron atoms
C. A vinegar and oil salad dressing
D. A disc of silicon with stones of germanium in it
Imani stirs a cup of hot sencha tea with a cool silver spoon. She notices that the silver spoon becomes warmer. What energy change occurs when the silver spoon is added to the hot cup of sencha tea?
A. The spoon adds its cold to the hot tea
B. The hot tea absorbs the heat from the spoon
C. The cool spoon causes the water to expand thus cooling it
D. The tea loses heat to the spoon causing the spoon to become warmer
Answer:
D. The tea loses heat to the spoon causing the spoon to become warmer
Explanation:
When the silver spoon at a lower temperature than the tea, is added to the tea, it makes thermal contact. Hence, the heat transfer starts between the two until the equilibrium is reached. We know that the heat transfer takes place from the body with a higher temperature to a body with a lower temperature. As a result, the body with higher temperature loses heat and its temperature lowers down. While the body with a lower temperature gains heat and its temperature rises.
Therefore, the correct option is:
D. The tea loses heat to the spoon causing the spoon to become warmer
Which wave must have a medium to travel?
A) light wave
B)compression wave
C) electromagnetic wave
D) ultraviolet wave
Explanation:
light waves because the categorised under mechanical waves
in the experiment it is important to make measurements that are both precise and accurate
which of these measurements of time is the most precise
5.1 second s
5.14 second s
5 second s.
A spring gun with a spring constant of 250N/m is compressed 5.0cm. How fast will a 0.025kg dart move when it leaves the gun?
Answer:
1.5 m/s
Explanation:
The dart moves when it leaves the spring gun with a velocity of 22.4 m/s.
What is Potential energy?Potential energy is defined as the stored energy that depends on the relative position of different parts of a system such as springs have more potential energy when it will be compressed or stretched.
For velocity calculation of the dart when it leaves the spring gun, using the formula for potential energy stored in a spring:
[tex]PE = (1/2)kx^2[/tex]
where,
k is the spring constant
x is the compression of the spring.
Since the spring is compressed by 5 cm, the potential energy stored in it is:
[tex]PE = (1/2)(250 N/m)(0.05 m)^2[/tex]
PE = 6.25 J
The potential energy stored in the spring will be transferred to the dart when it is released which can be calculated from the velocity of the dart using the equation of conservation of energy:
[tex]PE = (1/2)mv^2[/tex]
where,
m is the mass of the dart
v is its velocity.
Solving for v:
v = sqrt(2PE/m)
=> sqrt(2(6.25 J)/(0.025 kg))
=> 22.4 m/s.
Thus, the dart moves when it leaves the spring gun with a velocity of 22.4 m/s.
Learn more about Velocity, here:
brainly.com/question/25287332
#SPJ2
Question 4
1 pts
If you have a voltage of 120 volts entering your house and a light bulb with
0.625 amperes flowing through it, how many watts is your light bulb?
A. 50 watts
B. 150 watts
C. 25 watts
D. 75 watts
Answer:
D. 75 watts
Explanation:
brainliest please? i've just answered 3 of your questions and they were all correct! :) i hope i helped!
Answer:
(D) =75 WATTS
Explanation:
p(power)=i(current)×v(voltage)
p = 0.625 × 120
p =75 watts
please help me on my physics hw
Answer:
1. 11 A
2. 240 V
3. 8 Ω
4. 60 C
5. 14400 C
Explanation:
1. Determination of the current.
Voltage (V) = 110 V
Resistance (R) = 10 Ω
Current (I) =?
V = IR
110 = I × 10
Divide both side by 10
I = 110 / 10
I = 11 A
2. Determination of the voltage
Current (I) = 3 A
Resistance (R) = 80 Ω
Voltage (V) =?
V = IR
V = 3 × 80
V = 240 V
3. Determination of the resistance.
Current (I) = 0.5 A
Voltage (V) = 4 V
Resistance (R) =?
V = IR
4 = 0.5 × R
Divide both side by 0.5
R = 4 / 0.5
R = 8 Ω
4. Determination of the charge
Current (I) = 2 A
Time (t) = 30 s
Charge (Q) =?
Q = it
Q = 2 × 30
Q = 60 C
5. Determination of the charge.
We'll begin by converting 20 mins to seconds. This can be obtained as follow:
1 min = 60 s
Therefore,
20 mins = 20 × 60
20 mins = 1200 s
Finally, we shall determine the charge as follow:
Current (I) = 12 A
Time (t) = 1200 s
Charge (Q) =?
Q = it
Q = 12 × 1200
Q = 14400 C
Write any two uses of simple machines.
is wooden blocks transparent,translucent or opaque
Answer:
opaque
Explanation:
Materials such as wood, stone, and metals are opaque to visible light.
Blown balloon kept outside on a sunny day bursts what will happen to the ballon
When the balloon is kept in the sun, due to Sun's heat, the kinetic energy of gaseous particles inside the balloons also gets increased and the balloon expands. This will increase the pressure on the walls of the balloon. It continues to expand and comes to a stage when the baloon bursts.
Una caja con medicina es lanzada desde un avión localizado a una distancia vertical de 340 m por encima de un río. Si el avión lleva una velocidad horizontal de 70 m/s¿Qué distancia horizontal recorrerá la caja con medicina antes de caer al río?
Answer:
La distancia horizontal que recorrerá la caja con medicina antes de caer al río es 583.1 metros.
Explanation:
Una caja con medicina es lanzada desde un avión localizado a una distancia vertical de 340 m por encima de un río. Este movimiento posee una composición en dos dimensiones: uno horizontal sin aceleración, y el otro vertical con aceleración constante debido a la gravedad. Por lo que se trata de un movimiento rectilíneo uniforme (MRU) en su trayectoria horizontal o eje horizontal (es decir, su velocidad es constante) y un movimiento uniformemente variado (MRUV) en su trayectoria vertical o en el eje vertical (es decir, su aceleración es constante).
En este caso, son conocidos los datos, considerando el sistema de referencia de la imagen:
Vy = 0 m/s (trayectoria vertical) Vx = 70m/s (velocidad horizontal) hi = 340 m (altura inicial) g = -9,8 m/s² hf = 0 m (altura final. Cuando la caja de medicina cae al río, su altura será 0 m)En el caso del MRUV, la posición puede calcularse mediante la expresión:
Posición final= Posición inicial + Velocidad inicial*t + [tex]\frac{1}{2}[/tex]*a*t²
donde a es la aceleración y t el tiempo transcurrido.
En este caso, reemplazando los datos conocidos, teniendo en cuenta que el MRUV sucede en la trayectoria vertical y que la aceleración es el valor de la gravedad:
0 m= 340 m + 0 m/s*t + [tex]\frac{1}{2}[/tex]* (-9.8 m/s²)* t²
Resolviendo:
-340 m= [tex]\frac{1}{2}[/tex]* (-9.8 m/s²)* t²
[tex]\frac{-340 m}{\frac{1}{2} *(9.8\frac{m}{s^{2} } )} =t^{2}[/tex]
69.39 s²= t²
t= √69.39 s²
t= 8.33 s
La posición en MRU se obtiene mediante:
Posición final= Posición inicial + velocidad* tiempo
Con los datos conocidos y el tiempo calculado previamente, es posible calcular la distancia horizontal que recorrerá la caja con medicina antes de caer al río, siendo la posición inicial en x igual a cero:
Posición final= 0 m + 70m/s* 8.33 s
Posición final= 583.1 m
La distancia horizontal que recorrerá la caja con medicina antes de caer al río es 583.1 metros.
Veremos que la distancia horizontal que recorre la caja es 583.1 metros.
¿Como encontrar la distanca horizontal recorrida?Recordar que la velocidad vertical y horizontal son independientes.
Aqui, lo primero que debemos hacer es encontrar el tiempo que la caja tarda en llegar al suelo.
Para ello usamos la ecuación de movimiento vertical:
p(t) = (-4.9 m/s^2)*t^2 + v*t + h
Donde el primer termino representa la gravedad, el segundo la velocidad inicial (que es cero en este caso) y el tercero la altura inicial, que es 340m.
p(t) = (-4.9 m/s^2)*t^2 + 340m
La caja llegara al suelo cuando la función de arriba sea igual a cero:
(-4.9 m/s^2)*t^2 + 340m = 0
t = √(340m/(4.9 m/s^2)) = 8.33 s
Es decir, la caja tarda 8.33 segundos en llegar al suelo.
Esto significa que la caja se va a mover horizontalmente durante 8.33 segundos con una velocidad de 70m/s (la que tenía el avion). Es decir, la distancia horizontal que se mueve la caja es :
D = 8.33s*(70m/s) = 583.1 m
Sí quieres aprender más sobre ecuaciones de movimiento, puedes leer:
https://brainly.com/question/25316464
It took 3.5 hours for a train to travel the distance between two cities at a velocity of 120 km/h. How far did the train travel between the two cities?
Answer: 420 km
Explanation:
120 per hour, 3.5 hours
120 x 3.5 = 420
Which One don’t lie
Explanation:
heat but I dont see answer choices
which statement identifies a reason to preserves wetlands
Answer:
They store floodwater
Explanation:
PLEASE HELP ASAP
Compare the two waves. Wave A ___ (check all that apply)
Group of answer choices
has more energy
has a greater amplitude
has a lower amplitude
has a higher frequency
has less energy
has a lower frequency
Answer:
has more energy, has a greater amplitude, has a higher frequency
Explanation:
Sounds that reflect off of hard surfaces can create an echo.
O True
O False
Answer: True
Explanation:
When an electron is removed from a neutral atom, it becomes....
A) A positive ion
B) a negative ion
C) heavier
D) a bipolar atom
Answer:
A
Explanation:
at what point does the skater have the least amount of KE kinetic energy?
Answer:
I think it's D
Explanation:
because kinetic basically means moving and potential mean sitting still so ig it's c or D
what is Laminar flow??
Answer:
Explanation:
Laminar Flow is a very important topic discussed in physics in the subject of fluid dynamics. Basically, it explains how fluid particles behave at lower velocities. In such cases and when the viscosity of the fluid is low, the fluid particles flow smoothly in perfectly perpendicular layers that do not collide or cross each other. Unlike turbulent flow, which is the opposite. An example of Laminar flow can be seen when you open up a water hose with little pressure, the water simply flows out of the hose and looks very clear and smooth.
Identify the different parts of the face
Answer:
head
four head
hair
eyes
ears
nose
lips
chick
chin
eyebrow
eyelid
When heat moves from the ocean to the surrounding air, which is this an example of?
A the transfer of energy from the atmosphere to the hydrosphere
B the transfer of energy from the hydrosphere to the atmosphere
C the transfer of matter from the atmosphere to the hydrosphere
D the transfer of matter from the hydrosphere to the atmosphere
If someone replenishes the tree population in a forest ecosystem, how
might this affect the producers already living there?*
a: Increase in competitionfor biotic factors
b:decrease in competition for abiotic factors
c:increase in competition for abiotic factors
d: decrease in competition for biotic factors
Answer:
it would be c, an increase in competition for abiotic factors because if more trees are to be planted, less sunlight would seep through the leaves, leaving the producers to gain the abiotic factors to do with sunlight, temperature, and water
I hope this helps!!
have a wonderful day!
-millie :D
Qs 5 pleaseeee help!!!
Answer:
Ok, first is important that you understand how the heat radiation works.
All the objects that have some heat energy in them, radiate some of that energy in the form of electromagnetic waves.
Particularly, the Sun radiates a lot of energy (at the point that if you step under the sunlight, you can feel on your skin the heat that comes from the sun, this is due to radiation).
Now, suppose that you have a thin coat of water over you, then the material that gets impacted by that radiation will be the water and not you, and then the energy is dissipated (some of the energy goes to your body and some go to the air)
This is one way in which spraying water over themselves helps the elephants to keep them cool.
Another way in which heat can be transferred is by conduction.
When you have a hot object and a cool object, and you put them together (so the objects touch each other), the heat will flow from the hotter object to the cooler object until both objects have the same temperature.
Then if the elephant body temperature is larger than the temperature of the water that the elephant sprays over his body, when the water touches the body some of the heat in the elephant body will be transferred to the coat of water, and in this way, the temperature of the elephant's body decreases.
These are the two ways we wanted to find.
list and describe the units of power
Answer:
On the other hand, power is a scalar quantity and is basically the amount of energy consumed per unit time which has no direction.
Horsepower HP 746 watts
Kilowatts kW 1×103W
Megawatts MW 1×106W
Gigawatts GW 1×109W
The S.I unit of power is Watt(W) which is joule per second.
2 ways in which the effects of friction can be minimised in the experiment
Answer:
Friction can be minimized by using lubricants like oil and grease and by using ball bearing between machine parts. A substance that is introduced between two surfaces in contact, to reduce friction, is called a lubricant. Fluid friction can be minimized by giving suitable shapes to the objects moving in the fluids.
Explanation:
hope it helps
one end of a horizontal spring(k=80N/m)is held fixed while an external force is applied to the free end,stretching it slowly from×1=o to ×2=4cm.what is work done by the applied force on the spring
Answer:
6.4 Joules
Explanation:
For springs, Hooke's law states that;
F = ke
where F is a force applied, e is the extension and k is the spring constant.
Work done in a spring is the same as the potential energy stored in the spring. So that;
Work done = [tex]\frac{1}{2}[/tex] k[tex]e^{2}[/tex]
e = [tex]x_{2}[/tex] - [tex]x_{1}[/tex]
[tex]x_{2}[/tex] = 4 cm = 0.4 m
[tex]x_{1}[/tex] = 0
So that,
[tex]x_{2}[/tex] - [tex]x_{1}[/tex] = 0.4 m
Thus,
Work done = [tex]\frac{1}{2}[/tex] x 80 x [tex](0.4)^{2}[/tex]
= 40 x 0.16
= 6.4
Work done = 6.4 J
The work done by the force on the spring is 6.4 Joules.
Which scenario did not include a chemical change?
Answer:
what scenario i dont understand
Explanation:
step by step explenation
How does a mass drive work
Answer:
A mass driver or electro magnetic catapult is a proposed method of non-rocket space launch which would use a linear motor to accelerate and catapult payloads up to high speeds. All existing and contemplated mass drivers use coils of wire energized by electricity to make electromagnets.
Explanation:
may i be marked brainliest?
Explain how seafloor spreading is like a conveyor belt
Answer:
In sea-floor spreading, the sea floor spreads apart along both sides of a mid-ocean ridge as new crst is added. As a result, the ocean floors move like conveyor belts, carrying the continents along with them.
Explanation:
How would the motion of the book change if there was MORE friction as it moved across the table?
Answer:
The force of friction opposes the motion of an object, causing moving objects to lose energy and slow down.
Explanation: