Answer:
The correct option is momentum is conserved
Explanation:
A closed system is a system that is independent/free of external factors/force and does not exchange matter with its surrounding. Since a close system is free of external factors/force; acceleration is constant in it, mass is conserved in it and there will be changes in velocities of objects in the closed system.
This question actually seeks to test our knowledge of the law of momentum. The law of conservation of momentum states that the momentum of a closed system is conserved.
C: Momentum is consevered
A car accelerates from rest at a stop sign at a rate of 3.0 m/s^2 to a speed of 21.0 m/s, and then immediately begins to decelerate to a stop at the next stop sign at a rate of 4.0 m/s^2. How long did it take the car to travel from the first stop sign to the second stop sign? Show your work.
Answer:
t = 12.25 s
Explanation:
First we calculate the time taken by the car during accelerating motion, we use 1st equation of motion:
Vf = Vi + at₁
where,
Vf = Final Velocity = 21 m/s
Vi = Initial Velocity = 0 m/s
a = acceleration = 3 m/s²
t₁ = time taken during acceleration = ?
Therefore,
21 m/s = 0 m/s + (3 m/s²)t₁
t₁ = (21 m/s)/(3 m/s²)
t₁ = 7 s
Now, we use the same equation to find out the time taken during deceleration motion, with following data:
Vf = Final Velocity = 0 m/s
Vi = Initial Velocity = 21 m/s
a = deceleration = -4 m/s²
t₂ = time taken during deceleration = ?
Therefore,
0 m/s = 21 m/s + (-4 m/s²)t₂
t₂ = (-21 m/s)/(-4 m/s²)
t₂ = 5.25 s
Therefore, the total time taken by the car to travel from first stop sign to second stop sign is:
t = t₁ + t₂
t = 7 s + 5.25 s
t = 12.25 s
Answer:
12.25s
Explanation:
how water is constructed and how the matter is built-up?
Answer:
How is water constructed ?A molecule of pure water is made of two hydrogen atoms bonded to an oxygen atomHow is matter built-up?The basic building blocks that make up matter are called atoms. (hope i could help :)Explanation:
If an athlete completes a cycle around a circular track, his displacement eauals to ZERO.
O True
O False
The statement is TRUE.
"Displacement" means the distance and direction from the start-point to the end-point, NO MATTER how you got there.
If you go out cycling and go back home when you're done, your displacement is zero. it doesn't matter how far you cycled, or what streets or woods you cycled through, or whether your route was a circle, a square, an ellipse, a triangle, or a jumble, or whether you cycled around and around the same path 27 times. You ended right where you started. The distance from your start-point to your end-point is zero, so your displacement is zero.
What’s 2.3 miles into kilometers
Answer:
3.70149
Explanation:
The _____ optical illusion contains a horizontal line terminating in inward- or outward-pointing arrowheads.
Answer:
Muller-Lyer optical illusion
PLZ HELP TIMES TEST
When a person strikes and lights a match, potential energy in the match is transformed into which types of energy?
electrical and thermal
thermal and radiant
radiant and nuclear
nuclear and kinetic
Answer:
Thermal and Radiant
Explanation:
Thermal = Heat
Radiant = Light
Answer: B
Explanation:
6)
Calculate the area of a body which experiences a pressure of 60000 Pa by a force of 120N
Answer:
area = force by pressure
or, a = 120N by 60000 Pa
or, a= 0.002 m²
If a dog moves 3 meters due East and then 4 meters due North, what will be the dispalcement of the dog?
Answer:
5 mExplanation:
Displacement is the diatnce moves in a specified direction. It is the shortest distance covered by the dog. The displacement of the dog can be gotten by using the pythagoras theorem as shown;
According to the theorem, a²+b² = d² where d is the displacement
Substituting the given value into the fofrmula;
3²+4² = d²
9+16 = d²
d² = 25
square root both sides
√d² = √25
d = √25
d = 5 metres
Hence the displacement of the dog is 5metres
3. Daniel stands on a bridge over a river. He drops a coin and notes that the coin takes 3 s to reach the river below.
He must be standing
above the river.
A 10 m
B. 15 m
C. 30 m
D. 45 m
Answer:
45 m
Explanation:
Initial velocity of the coin = 0 m/s (since he dropped it from his hands)
time spent in falling - 3 sec
distance s = ?
using
s = ut + [tex]\frac{1}{2}[/tex]g[tex]t^{2}[/tex]
where
s is the distance the stone fell
u is the initial velocity
t is the time spent falling
g is acceleration due to gravity = 10 m/s^2 (positive downwards)
substituting values, we have
s = (0 x 3) + [tex]\frac{1}{2}[/tex](10 x [tex]3^{2}[/tex])
s = 45 m
6. Amy spits watermelon seeds at 1.8 m/s. How far will the seed travel in 1.2 s?
Answer:
2.16 meters
Explanation:
We can find distance using the following formula.
[tex]d=s*t[/tex]
where [tex]s[/tex] is the speed and [tex]t[/tex] is the time.
The speed of the watermelon seed is 1.8 meters per second. The time is 1.2 seconds.
[tex]s= 1.8 m/s\\t=1.2 s[/tex]
Substitute the values into the formula.
[tex]d= 1.8 m/s * 1.2 s[/tex]
Multiply. When you multiply the 2 "s" that represent seconds will cancel out.
[tex]d= 1.8 m * 1.2[/tex]
[tex]d=2.16 m[/tex]
The watermelon seed with travel 2.16 meters in 1.2 seconds.
scientific theories cannot change once they've been written down true or false
Answer:
Yes
Explanation:
Answer: false
a theory is just an idea, so it can be changed, while a scientific fact is true and wont be changed
. Explain how surface waves can have characteristics of both longitudinal waves and transverse waves.
Please use 3 content related sentences. (ref: p.388-393)
Answer:
This whole concept depends on the depends on the direction of propagation of the surface wave or displacement of wave such that if its in direction of wave velocity its said to features of longitudinal wave and if its in direction at 90° to wave velocity its said to have transverse features
A typical galaxy contains about 100 billion stars, and there are approximately 100 billion galaxies in the observable universe. About how many stars are in the observable universe
Answer = (100 billion stars/galaxy) x (100 billion galaxies/universe)
Answer = (100 billion x 100 billion) stars
Answer = 10,000 billion billion stars
Answer = 10,000,000,000,000,000,000,000 stars
Answer = 10²² stars/observable universe
The number of stars in the observable universe is; 10²² stars/observable universe.
How many stars are in the observable universe?Since there are about 100 billion stars in our galaxy; we can rewrite that to be;
100 billion stars/galaxy
However, there are about 100 billion galaxies in the observable universe.
Since our galaxy is one of the 10¹¹ observable galaxies in the universe; the number of stars in the observable universe is;
(100 billion stars/galaxy) x (100 billion galaxies/universe)
= (100 billion x 100 billion) stars
= 10,000 billion billion stars
= 10,000,000,000,000,000,000,000 stars
= 10²² stars/observable universe
Therefore, the number of stars in the observable universe is; 10²² stars/observable universe.
Read more the similar concept here;
brainly.com/question/24291110
#SPJ2
how does diffusion support the idea that matter is made up of particles
Explanation:
because when diffusion occurs it is as a result of the particles moving around freely in open space
The fact that matter is composed of particles and that these particles are incredibly tiny and have space between them supports the theory that matter is composed of particles.
What is diffusion?The mixing of materials is caused by the free movement of their particles is known as diffusion.
Even with a strong microscope, the substance is composed of microscopic particles that cannot be seen. The matter is anything that is both mass- and space-having. Small particles make up matter.
Because the particle's unrestricted movement in an open environment causes diffusion to happen.
Hence, diffusion supports the idea that matter is made up of particles.
To learn more about diffusion refer to;
https://brainly.com/question/13513898
#SPJ2
Conduction occurs when thermal energy is transferred by the movement of
a. Waves
b. molecules
c. liquids
d. fluids
Answer: Molecules
Explanation:
Answer:
B. molecules
Explanation:
got 100% on the edge quiz
. Air moves up and down by convection. Molecules of air are spaced farther apart in rising warm air. What must the volume of cold air have more of than the same volume of warm air?
Answer:d
Explanation:tsssss
What type of microscope bends light and uses multiple lenses to magnify a cell?
Choose 1 answer:
(Choice A) A Transmission electron microscope
(Choice B) B Simple light microscope
(Choice C) C Compound light microscope
(Choice D) D Scanning electron microscope
A speed skater moving to the left across frictionless ice at 8.0 m/s hits a 5.0-m-wide patch of rough ice. She slows steadily, then continues on at 6.0 m/s. What is her acceleration on the rough ice?
Answer:
Acceleration, [tex]a=-2.8\ m/s^2[/tex]
Explanation:
It is given that,
The initial speed of a speed skater, u = 8 m/s
The final speed of a speed skater, v = 6 m/s
Width of patch of rough ice, s = 5 m
We need to find the acceleration on the rough ice. Acceleration can be calculated using third equation of motion as :
[tex]v^2-u^2=2as\\\\a=\dfrac{v^2-u^2}{2s}\\\\a=\dfrac{(6)^2-(8)^2}{2\times 5}\\\\a=-2.8\ m/s^2[/tex]
So, the acceleration on the rough ice is [tex]2.8\ m/s^2[/tex]. Negative sign shows that its speed is decreased.
When a student stands on a rotating table,the frictional force exerted on the student by the table is?
Answer:
Less
Explanation:
because static friction is more than rolling friction
The displacement d (m) of a block sliding along a straight line is given by the equation d = -0.65 t + 0.21 t2, where t is the time in seconds. What is the instantaneous velocity of the block when t = 2.0 s?
Answer:
0.19m/sExplanation:
velocity is the change in displacement of a body with respect to time. Given the displacement d (m) of a block sliding along a straight line is given by the equation d = -0.65 t + 0.21 t², where t is the time in seconds, instantaneous velocity is expressed by differentiating the displacement with respect to time
Velocity = dd/dt
Velocity = -0.65 + 2(0.21)t²⁻¹
Velocity = -0.65 + 0.42t
The instantaneous velocity of the block when t = 2.0 s can be gotten by substituting t = 2.0s into the expression above:
Velocity = -0.65 + 0.42(2)
Velocity = -0.65 + 0.84
Velocity = 0.19
Hence the instantaneous velocity of the block when t = 2.0 s is 0.19m/s
What happens to scientific laws if new, unexpected data is discovered? a They become scientific theories. b They are revised. c Nothing, the new data is ignored.
Answer:
revised
Explanation:
A car starting from rest accelerates at a rate of 8 0 m/s/s. What is its final speed at the end of 40 seconda?
i have no idea what is if you know the answer, can you please answer it?
Answer:
you have to organize the data. a= acceleration vi=inicial velocity vf=final velocity t=time.
a=80m/s
vi=0
vf=?
t=40 s
the formula you have to use is:
vf=vi+a*t (final velocity= inicial velocity plus acceleration times time)
Explanation:
I was the best one at my class, hope it helped
Answer: 320 m/s
Explanation: V initial = 0, V final= ? Acceleration = 8m/s/s t=40s
So at the end of V 40 sec= v intial + acceleration x Δt = 0 +8m/s² x 40s = 320m/s8. An airplane heading to Paris from Houston travels 5000 miles at 500 mph. How long will it take the airplane to get to Paris?
Answer:
10 hours to get to Paris
If 2 different processes driven by heat transfer start at state 1 and end at state 2 BUT follow different paths, is the amount of energy transferred by heat the same for each path? Yes or no?
w
Trial
х
1
75.0 72.2
2
75.1
72.3
3
75.1 72.1
4
74.9
72.2
Which set of data is most likely the result of a systematic error?
Y
75.0
80.1
69.5
72.7
Z
86.2
86.7
71.5
70.8
w
Х
Z
Answer:
75
Explanation:
w
X
y
z.86.2,86.7,70.8
(100 POINTS AND BRAINLEIST) could you please help me with this ASAP!
The above are questions related to the formula of force F = m * a i.e. mass * accleration. It is defined by the Newton's second law of motion.
In the attachment, I can see that Question 1) and Question 2) are already done, So lemme start from Question 3[tex])[/tex]
3) Provided:-
Force applied = 7000 NOn a ball of mass = 0.5 kgTo FinD:-
Acceleration of the ball...?By using formula,
⇛ F = ma
⇛ 7000 N = 0.5 kg × a
⇛ a = 7000 / 0.5 m/s²
⇛ a = 14000 m/s²
So, the ball acclerates at the rate of 14000 m/s².
4) Provided:-
Accleration of the truck = 10 m/s²On a truck of mass = 31200 kgTo FinD:-
Force applied on the truck..?By using formula,
⇛ F = ma
⇛ F = 31200 kg × 10 m/s²
⇛ F = 312000 kg/m/s²
⇛ F = 312000 N
So, force on the truck = 312000 N
5) a) Force applied = 100 N
Mass applied = 5 kg
Then, Acceleration = 100 ÷ 5 = 20 m/s²
b) Force applied = 100 N
Mass applied = 10 kg
Then, Acceleration = 100 ÷ 10 = 10 m/s²
c) Force applied = 100 N
Mass applied = 20 kg
Then, Acceleration = 100 ÷ 20 = 5 m/s²
d) Force applied = 100 N
Mass applied = 50 kg
Then, Acceleration = 100 ÷ 5 = 2 m/s²
And we are done !!
#CarryOnLearning
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Answer: The answer are above :(
Please help with these physics problems 1. A soccer ball is dropped from the top of a building. It takes 5.8 seconds to fall to the ground. The height of the building is...? 2. The Falcon 9 launches to a height of 123 meters. What is its vertical initial velocity? 3. An apple falls from rest off a 10.m m tree. How long will it take before it hits the ground?
Answer:
1.) h = 164.8 m
2.) U = 49.1 m/s
3.) t = 1.43 seconds
Explanation:
1.) A soccer ball is dropped from the top of a building. It takes 5.8 seconds to fall to the ground. The height of the building is...?
Since the soccer ball is dropped from the building, the initial velocity U will be equal to zero
Using second equation of motion
h = Ut + 1/2gt^2
Substitutes the time into the formula
h = 1/2 × 9.8 × 5.8^2
h = 164.8 m
2. The Falcon 9 launches to a height of 123 meters. What is its vertical initial velocity?
At maximum height final velocity = 0
Using the third law of motion
V^2 = U^2 - 2gH
0 = U^2 - 2 × 9.8 × 123
U^2 = 2410.8
U = 49.1 m/s
3. An apple falls from rest off a 10.m m tree. How long will it take before it hits the ground?
Since the apple fall from rest, the initial velocity U will be equal to zero
Using the second equation of motion,
h = Ut + 1/2gt^2
substitute all the parameters into the formula
10 = 1/2 × 9.8 × t^2
10 = 4.9t^2
t^2 = 10/4.9
t^2 = 2.04
t = 1.43 seconds
science numerical problem .Hari drag a load a of 60 kg along a distance of 12 m . what amount of work does he do? as 0 mention the type of work
We don't know, and we don't have enough information to calculate it.
The weight of the 60kg load is (m g) = 588 Newtons.
IF Hari wanted to lift the load 12m straight up, he would have to do
(Force x distance) = (588 N) x (12 m) = 7,056 Joules of work.
But to drag it, he has to provide enough force to balance out the force of friction, and we don't know how much that is. It depends on the weight of the load, the shape of the load, the smoothness of the part of the load that sits on the ground, and the smoothness of the ground. But the only thing we know is the weight of the load.
a bee travels 7.6 m in 38 seconds. what is it’s velocity?
Answer:
Velocity=0.2m/s
Explanation:
Velocity=displacement / time
Velocity=7.6m/38s
Velocity=0.2m/s
what is the momentum in Kg m/s of a 10 kg truck travelling at A) 5 m/s B) 20 cm/s C) 36 km/h?
Answer:
A) 50 kg m/s
B) 2 kg m/s
C) 100 kg m/s
Explanation:
Recall that momentum is a physical quantity defined by the product of the object's mass times its velocity. Therefore, in our case the truck's momentum (p) is:
A) p = m * v = 10 kg * 5 m/s = 50 kg m/s
B) p = m * v = 10 kg * 0.20 m/s = 2 kg m/s (notice that the velocity in cm/s was converted into m/s before multiplying)
C) the conversion from km/h to m/s is a little more involved, so we taclke it first:
since 1 km = 1000 m and 1 hour = 3600 seconds, we convert 36 km/h by replacing each unit by its m and s expression as shown below:
[tex]36 \frac{km}{h} =36\,\frac{1000\,m}{3600\,\,s}=10\,\frac{m}{s}[/tex]
Then, the momentum is: p = m * v = 10 kg * 10 m/s = 100 kg m/s