Answer:
3,343.68kJExplanation:
Heat energy used up can be calculated using the formula:
H = mcΔt
m = mass oof the object (in kg) = 20kg
c = specific heat capacity of water = 4179.6J/kg°C
Δt change in temperature = 80-40 = 40°C
H= 20* 4179.6 * 40
H = 3,343,680Joules
H = 3,343.68kJ
Question 14 of 30
1 Point
Which of the following ideas was proposed by the ancient Greeks about 2500
years ago?
O A. Atoms consist of positive and negative charges.
O B. Atoms are indivisible units of matter.
OC. All atoms are alike.
O D. Atoms are composed of protons, neutrons, and electrons.
SUBMIT
Answer: a.
Explanation: i have done this before .. hope this helps (⌐■_■)
Answer:
B
Explanation:
HACE 2500 AÑOS NO SE CONOCÍAN LAS CARGAS ATÓMICAS.
if san andreas fault slips 2.5 cm each year how far would it separate in 100 years
Answer:
250cm or 2.5m
Explanation:
using direct variation
the length is = l
the time (year) = t
let k be the constant
so he have:
l=kt
2.5=k× 1
k= 2.5
Now in the next statement the 100 is given but not the length so
l=kt
~ l=k× 100 years
But k = 2.5
so :
l= 2.5×100
l= 250 cm
Hence it will be 250cm or 2.5m at which they will get separated
How does population density differ from population size?
а. Population size takes all organisms into account while population density only takes specific age
groups of the population into account
b. Population size is the total number of organisms, while population density is the total number of
organisms within a given area
C Population size is the total number of organisms within a given area, while population density is the
total number of organisms of a specific age
d. Population size is the total number of organisms of all species, while population density is the total
number of organisms of a specific species
Answer: B
Explanation:
Population size focuses on the size of the population. That is, the total number of organisms in a population.
While population density focuses on the density of the population. That is, mean number of organisms per unit area or volume.
Therefore, Population size is the total number of organisms, while population density is the total number of
organisms within a given area
A ball held 2.0 meters above the floor has 59 joules of potential energy the bald mass is about
Answer:
Mass of ball = 3.0102 Kg.
Explanation:
Potential energy at height h is given by
PE = mgh
where m is the mass of the body
g is the the acceleration due to gravity whose value is 9.8 m/s^2
h is the height from surface level
PE is potential energy
In the problem given h = 2 meters
PE = 59 joules
59 = m*9.8*2
=> m = 59/9.8*2 = 3.0102 Kg
Thus, mass of ball is 3.0102 Kg.
Answer:
3
Explanation:
Top person is wrong
just did lesson
List the 2 advantages and 2 disadvantages of wind as a source of electricity.
Answer:
The first 2 advantages of wind a source of electricity is that it provides you wifi and wind. 2 disadvantages of wind as a source of electricity is that to much wind could knock it down or slow down the source of the electricity.
Explanation:
I know this because i read a article on it.
A student is pushing a box across the room. To push the box three times farther, the student needs to do how much work?
Answer:
Removing some of the books reduced the mass of the box, and less force was needed to push it across the floor.
Which converts mechanical energy to electrical energy?
A. A flashlight
B. An electric motor
C. A generator
D. An electromagnet
Answer:
c. A Generator
Explanation:
The whole point of a generator is to produce electrical energy. The generator will use a mechanical motor usually running off of gas to produce electricity.
Which statement best compares the accelerations of two objects in free fall?
O The heavier object has a greater acceleration.
O The object that has the greater surface area has the lower acceleration,
The object that has the smaller mass has the greater acceleration.
O The objects have the same acceleration
Answer:
C. The object that has the smaller mass has the greater acceleration.
Explanation:
Two objects in free fall are accelerated due to gravity.
According to Newton's second law, if two objects with different masses have same force, then object with light or smaller weight will fall with greater acceleration while the object with greater mass will fall with less acceleration.
Hence, the correct option is C.
Answer:
c
Explanation:
its c
A 10 N block is at the bottom of a frictionless incline as shown to the right. How much work must be done against gravity to move it to the top of the incline?
600j
1000j
4800j
800j
Explanation:
We have,
According to attached figure, the height of the inclined plane is 60 m and force acting on the block is 10 N. It is required to find the work must be done against gravity to move it to the top of the incline. The work done is given by :
W = mgh
or
[tex]W=F\times h\\\\W=10\times 60\\\\W=600\ J[/tex]
Hence, the correct option is (A) "600 J".
Which of the following is an example of a device that uses a wheel and axle?
Check all that apply
A. frisbee
B. light bulb
C. doorknob
D. bicycle
(multiple answers)
Which is a resource that the National Park Service manages?
A. memorials
B. wildlife refuges
C. ecosystems
D. endangered species
Answer:
Which is a resource that the National Park Service manages?
A. memorials
B. wildlife refuges
Answer:
wildlife refuges
Explanation:
Antifreeze is a "must have" in an Albertan winter because it helps keep your vehicle engine from freezing in cold temperatures. Products such as antifreeze are composed of organic compounds that are classified as
a. alcohols
b. Esters
c. Carboxylic acids
d. Halogenated hydrocarbons
Products such as antifreeze are composed of organic compounds that are classified as alcohols. (a)
Maybe those other classes of chemicals also lower the freezing temperature of water, just like alcohol does. I don't know. But alcohol is what's used to make anti-freeze. I'm guessing alcohol must be cheaper, less toxic, and less corrosive inside the engines' cooling systems than any of that other stuff is.
what is the numerical value in meters per second squared of the acceleration of an object experiencing true free fall
Answer:
9.8m/s²
Explanation:
An object experiening a free fall is simply under the influence of gravity.
When an object is influenced by gravity, the object falls with an acceleration known as acceleration due to gravity.
This acceleration known as acceleration due to gravity has a constant value of 9.8m/s².
Can someone help me??
A car travels 1026 km in 6 hours. Find its average speed.
Answer:
171
Explanation:
To work out average speed, you have to do distance divide by time.
1026 divide by 6= 171
I hope that helped you.
The strong nuclear force is ?
Answer: Option B
Explanation:
The nuclear force is the strongest force in the universe. It is much more stronger than all the other forces and is 100 times stronger than the electric force.
The nuclear forces can be defined as the forces generated due to electron and protons in which the electrons have negative charge on it and the protons have positive charge on it.
Due to this force all the atoms and molecules, elements and compounds are held together.
To calculate the density of an object, which of the following values do you
need to know?
A. Volume
B. Buoyancy
C. Weight
D. Mass
Answer:
Volume I think
Explanation:
Answer:
A. volume and D. mass
Explanation:
Density is the amount of matter (mass) in a given space (volume).
The density of an object can be found using the following formula:
d=m/v
where m is the mass and v is the volume.
In order to find the density, you must know the mass and the volume of the object.
Therefore, the correct answers are A. volume and D. mass.
Tina and her puppy are tugging on a rope, each pulling on opposite ends.
When is Tina doing work?
O the entire time she plays with the puppy
o whenever she pulls the puppy toward her
O when she holds the rope steady as the puppy pulls it
O when she lets go of the rope and the puppy pulls it away
C. When she holds the rope steady as the puppy pulls it
Explanation:
because she is having to stay still as the force on the other end is pulling away, this is causing her body to work
According to the information, Tina is doing work when she holds the rope steady as the puppy pulls it. Thus, the correct option for this question is C.
What is work done in terms of physics?In terms of physics, work done may be characterized as the product of the component of the force in the direction of the displacement and the magnitude of this displacement. The formula for calculating work done is as follows:
Work done = Force (F) × Displacement (D).According to the context of this question, when Tina and her puppy are tugging on a rope, each pulling on opposite ends. The work done by both is estimated when they hold and pull the rope toward their side. The more they stretch the more work is performed by them.
Therefore, Tina is doing work when she holds the rope steady as the puppy pulls it. Thus, the correct option for this question is C.
To learn more about the Work done, refer to the link:
https://brainly.com/question/25573309
#SPJ6
How do Newton's laws of motion explain why it is important to keep the ice smooth on a hockey rink so that players can
pass a puck as quickly as possible?
OSmooth ice reduces the inertia of the hockey puck.
Smooth ice increases the force used to accelerate the hockey puck.
Smooth ice reduces the unbalanced forces that would slow the hockey puck.
Smooth ice decreases the reaction force that the ice exerts on the hockey puck.
Save and Fxit
Answer:
c
Explanation:
edge 2021
Which of the following is a difference between a law and a theory? A law can become a theory but a theory can never become a law. A theory is based on personal feelings but a law is based on testable evidence. A theory can predict the occurrence of a natural event with certainty but a law cannot. A law is usually a mathematical statement but a theory is a proposed statement.
Answer:
a theory is based on personal feelings but a law is based on testable evidence because a law is universal and constant fact of nature it is also an irrefutable theory a theory can become a law but a law can never become a theory it is based several scientific experimenrs
Explanation:
i hope this will help you
give one reason why the energy carries bu sound waves decreases as those sound waves travel through air
2. How far does a car travel in 90 seconds if it is traveling at a speed of 55 m/s?
Answer:
distance = speed × time
= 55m/s × 90s
= 4950 m
Which characteristics do temperate marine and temperate continental climates have in common? Check all that apply.
mild winters
hot summers
many tall trees
moderate amount of precipitation
two seasons with temperature differences
Answer:
moderate amount of precipitation
two seasons with temperature differences
Explanation:
Temperate marine climates is also known as oceanic climate and areas who experience this climate are closer to oceans. There is relative precipitation all round the year due to the close proximity to the water body and have the hot and cold season.
The temperate continental climate also has two season and relative rainfall but found in the areas along the Northern hemispheres.
Both climates have moderate amount of precipitation and two seasons with temperature differences.
Answer:
D
Explanation:
EDGE 2021
Jack rolled a marble down a ramp and recorded the potential energy and kinetic energy of the marble at different positions on the ramp, as shown in the table. Marble experiment Height of Marble from Ground (meters) Potential Energy of Marble (Joules) Kinetic Energy of Marble (Joules) Total Energy of Marble (Joules) Trial 1 1 1 3 4 Trial 2 2 3 1 4 Which is the independent variable in this experiment? Mass of marble Kinetic energy of marble Potential energy of marble Height of marble from ground
Answer: D
Height of marble from ground
Explanation:
From the formula of kinetic energy and potential energy,
K.E = 1/2mv^2
While
P.E = mgh
From all the parameters given from the question. You can see that mass is constant, acceleration due to gravity is also constant.
Independent variable must be a value that can varies.
Since Jack rolled a marble down a ramp and recorded the potential energy and kinetic energy of the marble at different positions on the ramp to see the effects on both energies.
This different position must be the height which will produce an effect on the potential and kinetic energy of the marble.
Independent variable always provides an effect for dependent variable. Which are kinetic energy and potential energy in this case.
Height of marble from ground is the right answer.
Answer:
The Correct Answer is D
Height of marble from ground
Explanation:
if earth were not tilted, would we still have seasons?
Answer:
Glad you asked that!
Explanation:
Actually,no.You see,if the earth was perfectly straight,then the northern hemisphere and southern hemisphere would have the same seasons,which is pretty much the world.But our world is tilted,so we happen to have differences for southern hemisphere and northern hemisphere.
Circuit questions. Plz help. Only answer is ok
Spaceship 1 and Spaceship 2 have equal masses of 300kg. They collide. Spaceship 1's final speed is 3 m/s, and Spaceship 2's final speed is 2 m/s in the same direction. What is their combined momentum? A. 600 kg-m/s B. 1,500 kg-m/s C. 1,200 kg-m/s D. 900 kg-m/s
Answer:
B. 1500 kg*m/s
Explanation:
Momentum p = m* v
In any type of collision, the total momentum is preserved!
The total momentum before and the total momentum after the collision is the same. We know the mass and speed after the collision so we can calculate the total momentum.
p1 + p2 =
m1*v1 + m2*v2
m1 = me = 300 kg
v1 = 3 m/s
v2 = 2 m/s
Substitute the given numbers:
300*3 + 300+2
900 + 600
1500 kg*m/s, which is answer B.
What is the inverse tangent of 0.9?
O A. 64.2
O B. 90.0
O C. 42.0
O D. 0.016°
Answer:
i think the aswers is C,
How may the desire for a perfect lawn related to environmental pollution
Answer:
Lawns are extremely costly in many ways, including dollars spent on them, the deadly ... Using lawn equipment also significantly adds to noise pollution. ... to all of the environmental damages, including water pollution, caused by fracking. ... ONE's ambition is to remain unbiased and to provide a good
Explanation:
Answer:
The gases from the lawn mower to mow the grass, weed killer toxicity affects, too much of the seeds to help grow your grass can actually harm your grass, etc.
Explanation:
A person is pulled to the right on a sled (total mass of 52.9 kg) across the surface of a frozen pond with a force of 67.7 Newtons so that they move with a constant velocity. What is the force of friction acting on the sled?
Answer:
67.7 N
Explanation:
Draw a free body diagram of the person on the sled. There are four forces:
67.7 N to the right,
friction force to the left,
weight force down,
and normal force up.
Constant velocity means 0 acceleration.
Sum of the forces in the x direction:
∑F = ma
67.7 N − F = 0
F = 67.7 N
Land masses that move on Earth are called: a. Continents b. Tectonic continents c. Tectonic plates d. Rock Masses HELP
Answer:
c. tectonic plates
Explanation:
Answer:
the answer is rock masses