Sound moves faster in warmer air than colder air the way bends away from the warm air and back towards of air.
Answer:
Sound travels slower in cold temperatures than in hot temperatures because the particles in cold air are more closely compacted together and move slower compared to the particles of hot air. Thus the sound, vibrations of particles in the atmosphere, will travel slower.
If a train goes at constant speed of 40 miles per hour for one hour, then at constant
speed of 55 miles per hour for two hours, what is its average speed at the train?
Answer: because the train goes 72 mph for 2 hours
Explanation:
does the train go 72mph for 2 hours as well? if so the answer would be 324 because you have to add 90 twice scene it goes at that speed for 2 hours thats 180. assuming the train goes 72 mph for 2 hours it would be 144. then add 180 and 144 and you get 324 merry christmas and a happy newyear to you and your family
How is ice more reflective than water??
Answer:
Because it has more texture and is solid. Its like glass
Explanation:
Answer:
Why is ice more reflective (has higher albedo) than liquid water? They're both the same substance (water). Is something quantum mechanical involved?
Explanation:
In fact ice is slightly less reflective than water. The reflectivity is related to the refractive index (in a rather complicated way) and the refractive index of ice is 1.31 while the refractive index of water is 1.33. The slightly lower refractive index of ice will cause a slightly lower reflectivity. In both cases the reflectivity is about 0.05 i.e. at an air/water or air/ice surface about 5% of the light is reflected.
“While the big bang theory is the most popular modern theory of how the universe formed, it is incomplete.” Which question does the big bang theory leave unanswered?
2. A police car drives from a police station to a distance of 170 km in 4 hours. He then stops at a gas station for 1 hour to fill gas and rest. Then the driver goes for 100 Km in 1 hour 30 minutes to his final destination.
a. What is the speed of the police car between the police station and the gas station?
b. What is the speed of the police car between the gas station and the final destination?
c. What is the average speed of the police car?
Answer:
a.42.5 km/h or .71 km/m
b. 66.7 km/h or 1.1repeating km/m
c.41.5 km/h or .69 km/m
Explanation:
These are all average speed problems, meaning you divide the distance traveled by the time [tex]s=\frac{d}{t}[/tex]
A. 170km/4hrs or 170km/240 mins
B. 100km/1.5hrs or 100km/90mins
C. The only tricky thing here is the question seems like it wants the speed for all of the information given, so you do include the one hour that he stops
270km/6.5 hrs or 270km/390 mins
Mass refers to the gravitational force on the matter in contact with the surface of a planet. true or false
Answer:
False
Explanation:
The mass of something does not depend on gravity. A planet has a constant gravitational force. Earth's is 9,80 N/kg. The moon, on the other hand, is 1,6 N/kg. the number of kilograms of something doesn't change if you go from one planet to another and since mass is measured in kilograms, mass doesn't change, therefore it does not refer to gravity. Mass refers to the quantity of matter in an object. It is weight that refers to the gravitational force on an object, since it is measured in newtons, and the amount of newtons per kilogram changes from planet to planet due to different gravity constants
What is the weight of a body at a centre of Earth
Help PLZ ;)
If the distance between two objects increases, what happens to the force of gravity between them?
(A) Increases
(B) Decreases
(C) Stays the same
Answer:
B) Decreases
Explanation:
Gravitational force is inversely proportional to distance. As distance between 2 objects increase, gravitational force between the 2 objects decreases.
Hope this helps!
Answer:
The answer would be B
Explanation:
Choose the law that BEST explains the example:
Throwing a ball with more force to increase acceleration is an example of Newton’s
first law?
2nd law
third law
none of these
PLEASE HELP ME ASAP!!!!!
Answer the question below. Use the rubric in the materials for help if needed.
After the American Revolution, why did many citizens, including the Anti-Federalists, argue that it was necessary to add a bill of rights to the U.S. Constitution? Use details to
support your answer.
Answer:
Federalists argued that the Constitution did not need a bill of rights, because the people and the states kept any powers not given to the federal government. Anti-Federalists held that a bill of rights was necessary to safeguard individual liberty.
Explanation:
i need one more brainliest
a car slows down from 50.0m/s to 20.0m/s in 60s what is the acceleration
Answer:
-2m/s^2
Explanation:
final velocity = 20m/s
initial velocity = 50 m/s
time taken = 60 s
20-50=30m/s
30/60 = -2
HELP RN PLEASSEEE!!! HELP!!
Choose all the answers that apply.
According to Newton's second law of motion:
1.objects at rest will remain at rest unless acted upon by an outside force
2.mass has an inverse relationship with acceleration
3.the greater the magnitude of force, the faster the acceleration
4.acceleration is caused by unbalanced forces
5.every action has an equal and opposite reaction
paper craft wall hanging how is it ?
Answer:
Nice
Explanation:
a pulling force carried by a rope is called what
Answer:
The pulling force that acts along a stretched flexible connector, such as a rope or cable, is called tension, T. When a rope supports the weight of an object that is at rest, the tension in the rope is equal to the weight of the object: T = mg.
Explanation:
In a certain semiconducting material the charge carriers each have a charge of 1.6 x 10-19
C. How many are entering the semiconductor per second when the current is 2.0 nA?
Answer:
1124923453 electrons
Explanation:
The formula for charge in coulomb ,C =Current in amperes, A * Time in seconds, s
Given in question ;
Charge = 1.6 * 10⁻¹⁹ C
Current = 2.0 nA = 2*e⁻⁹ A
Calculate time in seconds as
1.6 * 10⁻¹⁹ = 2*e⁻⁹ * t
1.6 * 10⁻¹⁹ /2*e⁻⁹ = t
6.48e⁻¹⁶ s = t
So using t=6.48e⁻¹⁶ s and current =2*e⁻⁹ A , the charge will be;
C = 2*e⁻⁹ * 6.48e⁻¹⁶ =1.799e⁻¹⁰ C
But 1 coulomb = 6.25 x 10¹⁸ electrons
so 1.799e⁻¹⁰ C = ?,,,,{ 6.25 x 10¹⁸} *{1.799e⁻¹⁰} = 1124923453.06 electrons
To get employees to work longer hours, employers often offer __________ in the form of extra pay.
A.
costs
B.
benefits
C.
incentives
D.
consequences
Answer:
C
Explanation:
I took the test
4. Hijackers are taking over a plane, They tell the pilot to get to Spain as fast as possible. The plane goes from 900
km/hr (beginning speed) to 1140 km/hr (final speed) in just 6 seconds. What is the acceleration of the plane?
What is the mass of a car if 4500N of force is used to accelerate it at a rate of 3.0m/s?
Answer:
The answer is 15,000 kgExplanation:
The mass of the car can be found by using the formula
[tex]m = \frac{f}{a} \\ [/tex]
f is the force
a is the acceleration
From the question we have
[tex]m = \frac{45000}{3} \\ [/tex]
We have the final answer as
15,000 kgHope this helps you
Why should you never do an exercise such as the bench press without a spotter?
Answer:
you could hurt yourself
Explanation:
Answer
You should never do an exercise such as the bench press without a spotter because you could hurt yourself or push your self too much.
Explanation:
what are two different examples of positive exeleration
Answer:Accelerating your car to get up to speed on a freeway
An airplane accelerating to take off
Accelerating out of the starting blocks at a track meet
Explanation:
How does changing the number of neutrons affect an atom?
Answer:
If you change the number of neutrons in an atom, you get an isotope of the same element. The addition of a neutron can make an atom radioactive. When you change the number of protons in an atom, you will change the atom from one element to a different element.
Explanation:
The characteristics of the atomic nucleus allow to find the answer for the effect of the change of neutrons in an atoms is
The change in neutrons changes the atomic mass.
A chemical element is made up of protons, neutrons and electrons; the first two are in the atomic nucleus and the electrons are in orbits around them.
The number of protons corresponds to the atomic number and its change changes the type of element.
The neutrons that are neutral charge together with protons form the mass of the atom, as neutrons are neutral if the number does not affect the type of atom, but if its atomic mass changes.
Elements with the same atomic number, but different atomic mass, different number of neutrons are called isotopes; in general all elements have isotopes, for example hydrogen has an isotope called deuterium that has a neutral and another radioactive isotope called tritium that has two neutrons.
In conclusion using the characteristics of the atomic nucleus we find the answer for the effect of the change of neutrons in an atoms is
The change in neutrons changes the atomic mass.
Learn more here: brainly.com/question/11673503
The photo shows dew drops that formed on the grass when temperatures
cooled during the night. Which change of state happened to form the dew?
A. Liquid to gas
B. Gas to liquid
C. Solid to gas
D. Gas to solid
Which dwarf planet orbits the Sun far beyond Pluto, taking 560 years per orbit?
Answer:
Eris
Explanation:
The object, temporarily designated 2003UB313 and later named Eris, orbits the sun about once every 560 years, its distance varying from about 38 to 98 AU.
Answer:
me
Explanation:
which one of the following is a derived SI unit?
A.newton B.meter C.mole d.Kilogram
Answer:
Meter
Explanation:
I'd say meters, cause it's the SI unit of length,
which is a Derived Quantity.
a resistance of 60ohms allows 0.4 amps of current to flow when it is connected across a battery. what is the voltage of the battery?
Answer:
V = 24 [V]
Explanation:
To solve this problem we must use ohm's law, which tells us that the voltage is equal to the product of resistance by the current.
V = I*R
where:
V = voltage [V]
I = current [amp]
R = resistance [ohm]
Therefore:
V = 0.4*60
V = 24 [V]
Please help my test is going on. Please answer both (i) and (ii).
Answer:
i. 7.5 m
ii. 15000 N
Explanation:
Area under vt graph shows the displacement
so area of triangle ABE= 1/2×15×2
=7.5 m
ii) F=ma
here, m=1000kg
and a=v-u/t
=15-0/1
a=15
F=1000×15=15000N
For his science project, Austin wants to determine if the pH of standing rainwater changes over time. He collects rainwater and distributes it evenly in 5 jars and places them all indoors in a spot that does not receive a lot of sunlight to limit evaporation. Using a pH testing kit, he measures the pH of the water in the first jar on the 4th day, second jar on the 8th day, third jar on the 12th day, fourth jar on the 16th day and fifth jar on the 20th day. What is the independent, or manipulated, variable in Austin's experiment?
Answer:
This question lacks options, the options are:
A. the number of days the rainwater was allowed to sit
B. the number of times the rainwater was observed
C. the change in the amount of rainwater due to evaporation
D. the change in pH of the rainwater over time
The answer is A
Explanation:
In an experiment, the independent variable is the variable that is changed or manipulated by the experimenter in order to effect a measurable response.
In this experiment, Austin is trying to determine how time changes the pH of standing rainwater. He collects rainwater and distributes it evenly in 5 jars, which he measured the pH at different days using a pH testing kit. Hence, the independent or manipulated variable is THE NUMBER OF DAYS THE RAINWATER WAS ALLOWED TO SIT before measuring their pH.
Forensic Science-Glass
Glass fragments may adhere to __ or __ used in
a break-in.
Answer:
a
Explanation:
i had this question on edge its the first one
idk actually
A wagon with a mass of 35 kg is pulled so that it accelerates from 0 m/s to 30 m/s in 15
seconds.
Remember to show all work!
a. What is the acceleration of the wagon?
b. What is the force required to get this acceleration?
Plz help me
Explanation:
a = v-u/t
a is the acceleration of the body
v is the final velocity
u is the initial velocity
t is the time
Given
v = 30m/s
u = 0m/s
t = 15secs
Substitute
a = 30-0/15
a = 30/15
a = 2m/s²
Hence the acceleration of the wagon is 2m/s²
b) Force = mass * acceleration
Given
Mas of the wagon = 35kg
acceleration a = 2m/s²
F = 35*2
F = 70N
Hence the force required to get this acceleration is 70N
The amount of matter in a substance or object is called:
??? What the answer
Answer:
mass!!
Explanation:
How would changing the mass of a bat affect a player’s ability to swing the bat and adjust the path of the bat to hit a moving baseball or softball?
Answer:
Explanation:
The answer to that question is "both," though past players tend to have used heavier bats than do today's players. Baseball's "king of swat" Babe Ruth reportedly began his hitting career using a 54 ounce (1.5 kg) hickory bat, and is known to have used a 40oz bat in 1927 when he hit his 60 home runs.[1] Ty Cobb and Joe Di Maggio both played with 42oz bats and Rogers Hornsby used a 50oz piece of lumber. George Sisler, playing for the St. Louis Browns in the 1920's, made his bat heavier by hammering Victrola needles into the barrel of his bat.[2] In the 1950's Cincinnati Reds' Ted Kluszeski hammered tenpenny nails into his bat to make it heavier.
Other great hitters including Ted Williams, Rod Carew and Stan Musial used much lighter bats: 31-33oz.[1] Roger Maris used a 33oz bat to hit his 61 home runs in 1961. Many players have tried to make their bats lighter by drilling a hole in the barrel and filling it with cork. Detroit Tigers' Norm Cash admitted to using a corked bat in 1961 when he won the batting title with a .361 average (though he slumped to .243 the next year with the same corked bat).[2]
Kirkpatrick[3] reports that Roger Maris participated in a 1962 experiment in which he batted for distance with 5 different new bats whose weights varied from 33 to 47oz. He hit 5 long fly balls with each bat and the distances were measured and correlated to bat weight. The heavier bats, on average, resulted in further distance. However, Maris' preferred bat (which he used to break Babe Ruth's home run record) was the lightest of the set, even though it produced the shortest distance fly balls. Mark McGwire used a 35oz bat to hit his 70 home runs in 1998, and Barry Bonds used a 32oz bat to hit his 73 home runs in 2001. Most of today's major league players typically use 31-35oz bats.
Physicists have shown,[3,4] from a simple collision analysis, that the optimum bat weight is between 15 and 18oz. However, no professional batter uses a bat this light (in fact, you cannot make a wood bat this light). NCAA regulations[x] recently imposed a -3 rule (length in inches minus weigh in ounces cannot exceed 3) so that 34 inch bats must weigh 31oz. So far no such rule exists for Little League play, and -12 composite bats were introduced for the 2003 season. This brings us back to our original questions: which is better: heavier or lighter bats? So, what is the optimum bat weight, and what criteria influence this choice? Let's start by looking at the collision between ball and bat.