The Universe is often studied by Scientist. The primary form of evidence that has led astronomers to conclude that the expansion of the universe is accelerating is the Observations of white dwarf supernovae.
There was the discovery of the faintness of high-redshift Type I supernovae by a team of scientist which showed that the expansion of the universe is accelerating.
The key evidence for that made scientist to talk about the expansion of the universe is accelerating comes from viewing and studying of white dwarf supernovae. It has been found that most distant stars all orbit at approximate speed as stars found about 30,000 light-years from their center.
Learn more about white dwarf from
https://brainly.com/question/12175185
PLEASE HELP FOR PHYSICS!
All objects exert a gravitational force on all other objects. This force is given by, F = GMm r2 , where the value of G = 6.673 × 10–11 N–m2/kg2 , M is the mass of the heavier object, m is the mass of the lighter object, and r is the distance between the two objects.
What is the force of gravity between two balls of mass 50 kg each if the distance between them is 25 m. Assume that there is no interference from any other gravitational field.
Hi there!
Recall Newton's Law of Universal Gravitation:
[tex]\large\boxed{F_g = G\frac{m_1m_2}{r^2}}[/tex]
Where:
Fg = Force of gravity (N)
G = Gravitational Constant
m1, m2 = masses of objects (kg)
r = distance between objects (m)
Plug in the given values stated in the problem:
[tex]F_g = (6.673*10^{-11})\frac{50 * 50}{25^2} = \boxed{2.669 * 10^{-10} N}[/tex]
HELPPP!! Thanks!
If you only wanted to increase the particle motion of a gas without increasing any of its other properties, which would the most correct situation?
a. Keep the gas at a constant pressure and keep the temperature constant, but increase the volume of the gas
b. Keep the gas in a fixed container at constant pressure and increase the temperature
c. Keep the gas in a fixed container at constant pressure and decrease the temperature
d. Keep the gas at a constant volume and keep the temperature constant, but decrease the pressure of the gas
Answer:c i think
Explanation: not sure
What does the horizontal line through the center of the wave on a graph represent?
Answer:
This is the midline or the medium which is the exact middle of the graphs minimum and maximum points(which are the amplitude)
Car 1 of mass m1 is waiting at a traffic light.
Car 1 is struck from behind by Car 2 of mass m2.
The two cars stick together after the collision.
Car 2 was traveling at v2i = 30.0 m/s before the collision.
What is the kinetic, in [J], of the system after the collision if m1 = 2500 kg and m2 = 1000 kg?
Answer:
Explanation:
Conservation of momentum
2500(0) + 1000(30) = (2500 + 1000)v
v = 8.57 m/s
KE = ½(2500 + 1000)8.57² = 128,571.428... = 128 KJ
The kinetic energy of the system after the collision would be 128.5 KJ.
What is momentum?It can be defined as the product of the mass and the speed of the particle, it represents the combined effect of mass and the speed of any particle, and the momentum of any particle is expressed in Kg m/s unit.
As given in the problem Car 1 of mass m1 is waiting at a traffic light.
Car 1 is struck from behind by Car 2 of mass m2. The two cars stick together after the collision. Car 2 was traveling at v2i = 30.0 m/s before the collision.
By using the conservation of the momentum,
2500(0) + 1000(30) = (2500 + 1000)v
v = 8.57 m/s
The final velocity of the system comes out to be 8.57 m/s.
The kinetic energy of the system after the collision,
KE =1/2×(2500 + 1000)×8.57² = 128,571.4
= 128.5 KJ
Thus, the kinetic energy of the system after the collision would be 128.5 KJ.
To learn more about momentum from here, refer to the link;
brainly.com/question/17662202
#SPJ2
Help me outttt pls and thanks
Calculate the net force acting on a body of mass 20 kg moving with a
uniform velocity of 4 ms-1.
Answer:
0 N
Explanation:
Uniform velocity means no acceleration and therefore no net force.
someone plz help
An object accelerates from rest to 93 m/s over a distance of 49 m. What acceleration did it experience?
Answer:
Explanation:
v² = u² + 2as
a = (v² - u²) / 2s
a = (93² - 0²) / (2(49))
a = 88.255102...
a = 88 m/s²
Section 1: Basic Energy Relationships
1. Click/tap the Start button and observe the motion. View the bar
charts and the velocity value as the coaster car moves. Complete
the following paragraph by entering total mechanical energy
(ME), kinetic energy (KE), and potential energy (PE). The
labeled locations refer to the graphic at the right.
As the coaster car rolls down the track from A to E, the
________ values decrease and the _______ value
increase and the ________ values remain constant. The
_______ is greatest at point A and smallest at point E.
However, the _______ is smallest at point A and largest
at point E.
Section 2: Hill Design
2. Click/tap on the Bumps tab at the top of the
Interactive. Then drag the grey circles to modify the
track so that it looks like the track design at the right.
Pay attention to the background grid to help with the
design. Note that Dot G is at the same height as Dot E;
make sure that the same is true of your final design.
3. Run the simulation. Does the coaster car travel as high
as point H? ___________ Give an explanation for why
it does or doesn't reach point H.
As the coaster car rolls down the track from A to E, the potential energy values decrease and the kinetic energy value increase and the total mechanical energy values remain constant. The potential energy is greatest at point A and smallest at point E. However, the kinetic energy is smallest at point A and largest at point E.
According the principle of conservation of mechanical energy, as the potential energy decreases, the kinetic energy increases.
[tex]P.E + K.E = M.A[/tex]
At point A, the coater has maximum potential energy.
At point E, the coaster has maximum kinetic energy.
We can fill the blanks as follows;
As the coaster car rolls down the track from A to E, the potential energy values decrease and the kinetic energy value increase and the total mechanical energy values remain constant. The potential energy is greatest at point A and smallest at point E. However, the kinetic energy is smallest at point A and largest at point E.
Based on the principle of conservation of mechanical energy, if the second simulation occurs at the same condition as the first, the height reached by coaster will be same.
Learn more about conservation of mechanical energy here: https://brainly.com/question/6852965
A 200-kg, 2.0-m-radius, merry-go-round in the shape of a flat, uniform, circular disk parallel to level ground is rotating at 1.2 cycles/second about an axis through its center of mass and perpendicular to the ground. A 50-kg boy jumps onto the edge of the merry-go round and lands at a fixed point. What is the angular velocity of the merry-go-round after the boy lands on it
Answer:
Explanation:
Conservation of angular momentum.
Disk I = ½MR²
Point mass I = mR² (boy)
Initial angular momentum
L₀ = Iω = ½MR²ω₀
Final angular momentum
L₁ = Iω = (½MR² + mR²)ω₁
as momentum is conserved, these are equal
(½MR² + mR²)ω₁ = ½MR²ω₀
ω₁ = ω₀(½MR²/ (½MR² + mR²))
ω₁ = ω₀(½M/ (½M + m))
ω₁ = 1.2(½(200)/ (½(200) + 50))
ω₁ = 1.2(⅔)
ω₁ = 0.8 cycles/second or 0.8(2π) = 1.6π rad/s
A block of mass m = 3.0 kg is pushed a distance d = 2.0 m along a frictionless horizontal table by
a constant applied force of magnitude F= 20.0 N directed at an angle 0= 30.0° below the horizontal
as shown in Figure. Determine the work done by (a) the applied force, (b) the normal force exerted
by the table, and (d) the net force on the block.
Explanation:
We apply the definition of work by a constant force in the first three parts, but then in the fourth part we add up the answers. The total (net) work is the sum of the amounts of work done by the individual forces, and is the work done by the total (net) force. This identification is not represented by an equation in the chapter text, but is something you know by thinking about it, without relying on an equation in a list.
The definition of work by a constant force is W=FΔrcosθ.
(a) The applied force does work given by
W=FΔrcosθ=(16.0N)(2.20m)cos25.00=31.9J
(b), (c) The normal force and the weight are both at 900 to the displacement in any time interval. Both do 0 work.
(d) ∑W=31.9J+0+0=31.9J
a 4kg sample of water absorbs 500 joules of energy.How much did the water temp change.The specific heat of water is 4200 J/(kg C)
Answer:
0.02976°C
Explanation:
Heat Supplied = mcø
ø = 500/(4*4200)
ø = 0.02976 °C
half-life questionnnnn:
A gazelle is grazing while standing in a fixed location. When it's startled by a predator, the gazelle accelerates uniformly for 16.8 s until it reaches a speed of 21.9 m/s. The gazelle then runs in a straight line at constant speed for an additional 16.4 s. Finally, it uniformly slows to a stop at a rate of 1.8 m/s/s. What is the total distance traveled by the gazelle in meters
Answer:
Explanation:
acceleration phase
average speed was 21.9/2 = 10.95 m/s
distance covered is 10.95 m/s(16.8 s) = 183.96 m
distance at top speed 21.9 m/s(16.4 s) = 359.16 m
distance while decelerating (0² - 21.9²)/(2(-1.8)) = 133.225 m
total = 183.96 + 359.16 + 133.225 = 676.345 = 676 m
One potato plant makes 7.5
potatoes. There are 10.000
people on a ship and 3
potatoes per person. How
many potato plants are
needed per person.
If all conditions are ideal, you may harvest about five to 10 potatoes per plant for your gardening efforts. Yields are based on both the care your give your plants during the growing season and the variety of potatoes you choose to grow.
answer
7.5×10.000=75÷3=25
The density of water is 1000 kg/m the pressure pf water at 10 m depth is about
Answer:
pressure in liquids is given as:
P= hpg
where h is the depth
where p is the density
where g is 10
Explanation:
From the formula above
p = 10 X 1000 X 10
p = 100000N/m
The more matter in an object, the _____.(1 point)
lower its weight and mass
lower its weight and mass
more likely it is to have gravity
more likely it is to have gravity
greater its gravitational attraction to Earth
greater its gravitational attraction to Earth
less likely it is to have weight on the moon
Answer:
more likely it is to have gravity
Which car is experiencing negative acceleration?
A. a car sitting at a red light
B. a car slowing down as it approaches a red light
C. a car driving in a circle at a constant speed
D. a car changing its speed from 0 km/hr to 10 km/hr
Answer:B
Explanation:
Answer: b
Explanation: b as it slows down and decelerates
How much tension must a rope withstand if it is used to accelerate a 1710-kgkg car horizontally along a frictionless surface at 1.30 m/s 2 m/s2
Answer:
Explanation:
Lowest tension will occur when the rope is also horizontal.
F = ma
F = 1710(1.30)
F = 2223 N
Which is an electromagnetic wave A. The waves that heat a cup of water in a microwave oven B. A flag waving in the wind C. Turning on a flashlight D.The changes in the air that result from blowing a horn
Answer:
The answer would be A. The waves that heat a cup of water in a microwave oven
A student removed a wool hat from her head. Her hair stood up from static electricity. What did her hat do to cause this
Answer:
A student removed a wool hat from her head. Her hair stood up from static electricity. What did her hat do to cause this? ... Yes, the motor would run faster because the increased electrical force increases the magnetic force in the motor.
A student removed the wool from her head due to the static charge of electricity, it is caused.
What is charge?A difference in electric charge within, on the surface of, or between two materials results in static electricity. Until it can be expelled through an electrical discharge or current, the charge stays. In contrast to current electricity, which transmits energy by letting an electric charge flow through a conductor or a space, static electricity does not transport energy.
When two surfaces come into contact, wear, and separate from one another when at least a single surfaces has a good resistance to electric current, a static electrostatic attraction can be produced. Because individuals can feel, hear, and even see a spark when the extra charge is neutralized when placed close to a powerful electrical conductor, most people are familiar with static electricity's effects.
To know more about charge :
https://brainly.com/question/19886264
#SPJ5
AP Physical problem the wording is really throwing me off and im totally lost on how to do this. I would love some help please and thank you!
Explanation:
a) Here is the free-body diagram. Note that I included the components of the weight mg (shown in dotted arrows) for use in the other parts of the problem.
b) The component of the weight parallel to the plane (shown in the diagram as a dotted arrow along the x-axis) is [tex]mg\sin15[/tex] and it is equal to
[tex]mg\sin15 = (25\:\text{kg})(9.8\:\text{m/s}^2)\sin15 = 63.4\:\text{N}[/tex]
c) Applying Newton's 2nd law to the y-axis, we can write
[tex]y:\;\;\;N - mg\cos15 = 0 \Rightarrow N = mg\cos15[/tex]
[tex]N = (25\:\text{kg})(9.8\:\text{m/s}^2)\cos15 = 236.7\:\text{N}[/tex]
d) The component of the weight mg into the plane is the same as the normal force, hence it's also 236.7 N.
e) To solve for the coefficient of friction, we apply Newton's 2nd law to the x-axis:
[tex]x:\;\;\;mg\sin15 - F_f = 0[/tex]
[tex]\Rightarrow F_f = mg\sin15\;\;(2)[/tex]
where [tex]F_f[/tex] is the frictional force defined as [tex]F_f = \mu N[/tex] so we can use Eqn(1) on Eqn (2) to write
[tex]\mu (mg\cos15) = mg\sin15[/tex]
Solving for [tex]\mu,[/tex] we get
[tex]\mu = \dfrac{\sin15}{\cos15} = \tan15 = 0.27[/tex]
An object of mass 6.36 kg is released from rest and drops 2.05 m to the floor. The collision is completely inelastic. How much kinetic energy is lost during the collision
Answer:
Essentially all of it
Explanation:
The potential energy was
PE = mgh = 6.36(9.81)(2.05) = 127.90278 = 128 J
ignoring air resistance, this PE converts to KE
With no rebound final velocity is zero, so Kinetic energy lost = 128 J
How much work does an elephant do while moving a circus wagon 60 meters with a pulling force of 240N
Answer:
14,400
Explanation:
You need to do 240x60 and you would get the answer as 14,000
A wheel with radius 41.5 cm rotates 5.13 times every second.
Find the period of this motion.
What is the tangential speed of a wad of chewing gum stick to the rim of the wheel?
The tangential speed of a wad of chewing gum to the rim of the wheel is approximately 1337.659 centimeters per second.
Let suppose that the wheel rotates at constant angular speed ([tex]\omega[/tex]), in radians per second, the tangential speed of a wad of chewing gum to the rim of the wheel ([tex]v[/tex]), in centimeters per second, is:
[tex]v = 2\pi\cdot r\cdot f[/tex] (1)
Where:
[tex]r[/tex] - Radius of the wheel, in centimeters[tex]f[/tex] - Frequency, in hertzIf we know that [tex]f = 5.13\,hz[/tex] and [tex]r = 41.5\,cm[/tex], then the tangential speed of the chewing gum is:
[tex]v = 2\pi\cdot (41.5\,cm)\cdot (5.13\,hz)[/tex]
[tex]v \approx 1337.659\,\frac{cm}{s}[/tex]
The tangential speed of a wad of chewing gum to the rim of the wheel is approximately 1337.659 centimeters per second.
To learn more on angular speed, we kindly invite to check this verified question: https://brainly.com/question/9684874
Describe a vibration that is not periodic. NO LINKS PLEASE
Answer:
1)The position change of almost any manually operated room light switch.
2) Sunlight striking a point on the ground on a partly cloudy and windy day
Explanation:
3. A 1500 kg car moving at 30 m/s strikes a 6000 kg van initially at rest. If the car
comes to a complete stop after the collision, what is the final velocity of the van?
Answer:
7.5m/s
Explanation:
Force= mass × velocity
Energy is conserved, the car and van should have the same overall force.
1500kg × 30m/s= 6000kg × final velocity
Final velocity = 7.5m/s
Are these a Chemical or Physical Change??
1. Sodium Bicarbonate breaks down into sodium carbonate and water.
A. Chemical Change
B. Physical Change
2. Mercury is cooled until it is in the solid state.
A. Chemical Change
B. Physical Change
The change of sodium bicarbonate breaking down into sodium carbonate and water is a chemical change. The cooling of mercury until it is in the solid state is physical change. The correct option for 1 is A and for 2 is B.
What is chemical and physical change?A chemical change occurs as a consequence of a reaction, whereas a physical change occurs when transformation occurs forms but retains its chemical identity.
Chemical changes include burning, cooking, rusting, and rotting. Physical changes include boiling, melting, freezing, and shredding.
A physical change is required to a specimen of matter in which some of the material's properties change but the matter's identity does not.
Physical changes can be classified as either reversible or irreversible. Melting is a reversible physical change because the melted ice cube can be refrozen.
In the first case, sodium bicarbonate is breaking down and forming sodium carbonate and water, this implies a chemical change.
In the second case, mercury is just cooling down, changing its physical shape. So it is physical change.
Thus, the correct option for 1 is A and for 2 is B.
For more details regarding chemical and physical changes, visit:
https://brainly.com/question/11321843
#SPJ2
What is work? A. What happens when energy is destroyed B. The number of molecules in a substance C. The total size of an object divided by its mass D. What happens when a force causes an object to move
Answer:
Which extended definition would be most helpful to add to this body paragraph?
Laughter Yoga, a new form of yoga, is becoming increasingly popular.
Laughter Yoga, which is becoming more and more popular, was created in the 1990s.
Laughter Yoga is modeled after traditional yoga but includes laughter exercises.
Laughter Yoga is a form of yoga that was created by Dr. Madan Kataria in the 1990s.
Explanation:
c
Name the energy possessed by hot air
Answer:
geothermal energy
Explanation:
the energy is obtained from the heat within the surface of earth
Answer:
heat energy
Explanation:
which one would cool down faster, water or a block of concrete? why?
Answer:
If you mean by temperature
Water, cause say the water just sits there, it'll take a few minutes to cool down. But for concrete having all the hot sun rays on it during summer, can make it very hot, if you put 'cold water' there, it'll only last there for a moments (and that's by effect not waiting), if you wait for it to cooldown by itself, it'll take quite awhile.
If you mean solidify:
The stuff required to make concretes takes HOURS and HOURS to finish solidifying, unlike water being turn into ice normally only takes about half an hour or an hour (maybe 2) in the freezer (I don't know how long for ice, but not long at all in comparison to concrete).
Explanation:
Explanation was mostly part of the answer