When the brake is applied to the car and comes to rest after some time is an example of an object that is slowing down.
What is acceleration?The rate of change of velocity with respect to time is known as acceleration. According to Newton's second law, the eventual effect of all forces applied to a body is its acceleration.
1. When the brake is applied to the body and comes to rest after some time is an example of an object that is slowing down.
2. When a person accelerates the car and the velocity is increasing is an example of speeding up.
3. An object moves in a circular motion moving at a constant speed but changing direction,
4. Acceleration is the rate of change of velocity. If the change in the velocity is constant the acceleration is zero is an example of moving at a constant velocity with zero acceleration.
To learn more about acceleration, refer to the link;
https://brainly.com/question/2437624
#SPJ1
Q7 Explain how light can be reflected at lots of different angles from a rough surface and still obey the law of reflection. Use a diagram in your answer.
Q8 Read the following statements.
A: You can have refraction without dispersion
B: You cannot have dispersion without refraction
a Discuss a situation where statement A is true.
b Discuss a situation where statement B is true.
Q9 A light year is the distance that light travels in a year. It takes light about 8.3 minutes (or 500 seconds) to travel the 150 million km from the Sun. a Calculate how far light travels in 1 second.
b The Moon is 1.3 light seconds from Earth. Calculate how far away it is in km.
Explanation:
Q7Answer=If light meets a rough surface, each ray obeys the law of reflection. However, the different parts of the rough surface point in different directions, so the light is not all reflected in one direction. Instead, the light is reflected in all directions. This is called diffuse scattering .
Car B is being pushed by a force of 22000 N. If it has a mass of 1375 kg.,
what is the acceleration of this car?
Answer:
a = 16 m/s²
General Formulas and Concepts:
Dynamics
Newton's Law of Motions
Newton's 1st Law of Motion: An object at rest remains at rest and an object in motion stays in motion Newton's 2nd Law of Motion: F = ma (Force is equal to [constant] mass times acceleration) Newton's 3rd Law of Motion: For every action, there is an equal and opposite reactionExplanation:
Step 1: Define
Identify variables
[Given] F = 22000 N
[Given] m = 1375 kg
[Solve] a
Step 2: Find Acceleration
Substitute in variables [Newton's 2nd Law of Motion]: 22000 N = (1375 kg)aIsolate a: 16 m/s² = aRewrite: a = 16 m/s²This is the last 2 questions i need! It’s due in 10 minutes please help!! I will mark brainliest asap
Answer:
I don't know 11 but in no. 10,
The ans is 3.66
Total distance = 10m+30m+15m = 55m
Total time = 5secs+7secs +3secs =15secs
Av speed = d/t =55/15 = 3.66 m/s
The school bag of four students A,B,C,D measures 9kg, 2800gm, 2kg and 8000gm respectively. Whose bag is the lightest
Answer:
Student C
Explanation:
order from heaviest to lightest is...
9 kg (A) , 8000g (8 kg) (D) , 2800g (2.8kg) (B), 2 kg (C)
The diagram show three different types of walls that could be built in a house. Through which hall would the heat lost be maximum.
Answer:
the thin steel wall because that wall is so very to fast broke
Aiden is writing a report about the structure of the atom. In her report, she says that the atom has three main parts and two subatomic particles. Do you agree with her? Why or why not?
Answer:
I don't agree
Explanation:
Atoms have 3 subatomic particles protons, electrons and neutrons,
The momentum of an object is 2.5 kg•m/s, and it is travelling at a speed of 100 m/s.
a) What is the mass of the object?
Answer:
Refer to the attachment!~
unequal length of day and night
Rotation or Revolution
Một vật chuyển động thẳng biến đổi đều đi hết quãng đường AB trong thời gian 6 giây. Vận tốc của vật khi đi qua điểm A là 5m/s, khi đi qua điểm B là 15m/s. Tìm chiều dài của quãng đường AB. A. 50 m B. 80 m C. 60 m D. 70 m →→→
Câu trả lời:
C. 60 m
Giải trình:
Cho rằng:
Tốc độ tại A, u = 5m / s
Tốc độ tại B, v = 15m / s
Độ dài quãng đường, AB =?
Tổng thời gian di chuyển = 6 giây
Hãy tính gia tốc, a:
a = (v - u) / t
a = (15 - 5) / 6
a = 1,667 m / s²
Từ :
v² = u² + 2aS
Trong đó, S = khoảng cách
15² = 5² + 2 (1.667 * S)
225 = 25 + 3,334S
225 - 25 = 3,334S
200 = 3,334S
S = 200 / 3,334
S = 59,98 m
S = 60 m
When you flip a penny (2.35 g), it leaves your hand and moves upward at 2.85 m/s. Use energy to find how high the penny goes above your hand before stopping. A (b) The penny then falls to the floor, 1.26 m below your hand. Use energy to find its speed just before it hits the floor. A (c) Explain your choice of reference level for parts (a) and (b). C (d) Choose a different reference level and repeat part (b)
Answer:
a. 0.41 m
b. 5.72 m/s
c. i. For part (a), I chose the hand as the reference level since the penny was thrown from the hand and the height of the penny at the hand is zero and also, it is easier to calculate from a zero reference level.
ii. For part (b), I chose the ground as the reference level since the height of the penny above the ground is positive and the height of the penny when the penny hits the ground is zero and also, it is easier to calculate from a zero reference level.
d. 5.72 m/s
Explanation:
a. Use energy to find how high the penny goes above your hand before stopping.
Taking the hand as the ground level, and from the law of conservation of energy, the total mechanical energy at the hand, E equals the total mechanical energy when the penny stops in the air, E'.
E = E'
U + K = U' + K' where U = initial potential energy at hand level = mgh where h = height at hand level = 0, K = initial kinetic energy at hand level = 1/2mv² where v = speed at hand level = 2.85 m/s, U' = final potential energy at stopping level = mgh' where h' = height at stopping level, K = final kinetic energy at stopping level = 1/2mv'² where v = speed at stopping level = 0 m/s (since the penny momentarily stops)
So, U + K = U' + K'
mgh + 1/2mv² = mgh' + 1/2mv'²
substituting the values of the variables into the equation, we have
mg(0) + 1/2m(2.85 m/s)² = mgh' + 1/2m(0 m/s)²
0 + 1/2m(8.1225 m²/s²) = mgh' + 0
m(4.06125 m²/s²) = mgh'
h' = 4.06125 m²/s² ÷ g
h' = 4.06125 m²/s² ÷ 9.8 m/s²
h' = 0.41 m
(b) The penny then falls to the floor, 1.26 m below your hand. Use energy to find its speed just before it hits the floor.
Taking the hand as the ground level, and from the law of conservation of energy, the total mechanical energy when the penny stops in the air, E' equals the total mechanical energy on the ground, E"
E' = E"
U' + K' = U" + K" where U' = initial potential energy at stopping level = mgh" where h' = height at stopping level = height of penny above hand, h' + height of hand above ground = 0.41 m + 1.26 m = 1.67 m, K = initial kinetic energy at stopping level = 1/2mv'² where v = speed at stopping level = 0 m/s (since the penny momentarily stops), U = final potential energy at ground level = mgh₁ where h₁ = height at ground level = 0, K = final kinetic energy at ground level = 1/2mv"² where v" = speed at ground level,
So, U' + K' = U' + K'
mgh" + 1/2mv'² = mgh₁ + 1/2mv"²
substituting the values of the variables into the equation, we have
mg(1.67 m) + 1/2m(0 m/s)² = mg(0) + 1/2mv"²
1.67mg + 0 = 0 + 1/2mv"²
1.67mg = 1/2mv"²
1.67g = 1/2v"²
v"² = 2(1.67g)
v" = √[2(1.67g)]
v" = √[2(1.67 m × 9.8 m/s²)]
v" = √[2(16.366 m²/s²)]
v" = √[32.732 m²/s²)]
v" = 5.72 m/s
(c) Explain your choice of reference level for parts (a) and (b).
i. For part (a), I chose the hand as the reference level since the penny was thrown from the hand and the height of the penny at the hand is zero and also, it is easier to calculate from a zero reference level.
ii. For part (b), I chose the ground as the reference level since the height of the penny above the ground is positive and the height of the penny when the penny hits the ground is zero and also, it is easier to calculate from a zero reference level.
(d) Choose a different reference level and repeat part (b)
Taking the hand as the ground level, and from the law of conservation of energy, the total mechanical energy when the penny stops in the air, E' equals the total mechanical energy on the ground, E"
E' = E"
U' + K' = U" + K" where U' = initial potential energy at stopping level = mgh' where h' = height at stopping level = 0.41 m, K = initial kinetic energy at stopping level = 1/2mv'² where v' = speed at stopping level = 0 m/s (since the penny momentarily stops), U = final potential energy at ground level = mgh₁ where h₂ = height of hand above the ground level = height of ground below hand = -1.26 m(it is negative since the ground is below the hand), K = final kinetic energy at ground level = 1/2mv"² where v = speed at ground level,
So, U' + K' = U' + K'
mgh' + 1/2mv'² = mgh₂ + 1/2mv"²
substituting the values of the variables into the equation, we have
mg(0.41 m) + 1/2m(0 m/s)² = mg(-1.26 m) + 1/2mv"²
0.41mg + 0 = -1.26 mg + 1/2mv"²
0.41mg + 1.26mg = 1/2mv"²
1.67mg = 1/2mv"²
1.67g = 1/2v"²
v"² = 2(1.67g)
v" = √[2(1.67g)]
v" = √[2(1.67 m × 9.8 m/s²)]
v" = √[2(16.366 m²/s²)]
v" = √[32.732 m²/s²)]
v" = 5.72 m/s
What is kinetic and potential energy?
Answer:
the energy produced in a body due to its motion is kinetic energy.
energy produced in a body due to its position is potential energy.
Explanation:
kinetic energy is the energy possessed by a body in motion
Potential energy is the energy possessed by a body by virtue of its position with respect to a reference level
The weight of a girl on the Earth is 340 N, what is her mass on Earth?(g= 10Nkg-1)
Answer:
34 kg is the answer to the question
Which of the following refers to friction that acts on an object that is not moving? O A. Kinetic friction O B. Inertia O c. Contact force O D. Static friction
HELP PLEASE!!
Answer:
D.STATIC FRICTION
Explanation:
Have a nice day
dimension of radius of sphere
Answer:
The dimension is L
Explanation:
Dimension analysis is a method of representing quantities majorly with respect to some fundamental quantities of mass (M), length (L), time (T).
A sphere has a definite volume which relates to its radius by:
V = [tex]\frac{4}{3}[/tex][tex]\pi[/tex][tex]r^{3}[/tex]
In this equation [tex]\pi[/tex] is a dimensionless quantity, and the unit of v is [tex]m^{3}[/tex].
But, metre is a measure of length, thus it has a dimension of L.
So that,
[tex]m^{3}[/tex] ≅ [tex]L^{3}[/tex]
Then,
[tex]L^{3}[/tex] = [tex]r^{3}[/tex]
Find the cube root of both sides to have,
r = L
Therefore, the dimension of the radius of a sphere is L.
What is the difference between potential and kinetic types of energy? 1 pois
Answer:
Potential energy is energy that is stored in an object or system. It remains unaffected by the environment outside of the object or system. Kinetic energy is the energy of an object or a system's particles in motion.
Explanation:
Rewrite the false statements correctly
1.If an object sinks in one liquid and floats on another liquid,it implies that the density of second liquid is less than the first liquid.
2.The immersed volume of body in a liquid depends on density of the liquid.
3.Relative density of a body is usually expressed in kgm^-3
Explanation:
1. if an object sjnks in one liquid and floats on another liquid it implies that the density of second liquid is greater than the density of first liquid
Which statement describes how chemical formulas, such as H20, represent compounds?
Answer:
They show the elements that make up a compound.
They show the three-dimensional shape of a molecule.
They show the types of atoms that make up a molecule.
They show the number of each type of atom in a molecule.
Explanation:
❣️(◍Jess bregoli◍)❣️#keep learning!!
hey what is Krichoff rule
good morning
Explanation:
sorry I've got a bad hand writing but i think ull understand more with the screenshot that I've just pinned for u there
Answer:
this guy has answed ur question lol
1) the wavelengths property that makes it possible for sound to be heard around a bend is A) diffraction. B) Reflection C) refraction. D) interference
2) which property of sounds do bats use to detect their paths?
A) Diffraction B) reflection C) Refraction D) interference
please give a reason or an explanation for each answer you choose
Answer:
1. A
2. B
Explanation:
Sound are mechanical waves that are highly dependent on matter for their propagation and transmission.
Sound travels faster through solids than it does through either liquids or gases.
Wavelength can be defined as the distance from one peak to the next peak of a waveform. This distance is also equal to the distance from one trough of a wave to another.
Diffraction is a wavelength property that makes it possible for sound to be heard around a bend. Thus, it's a property that causes a change in the direction of a wave as it travels through or around a barrier (obstacle) in its path.
Simply stated, diffraction involves the bending of waves around small obstacles with their dimensions smaller than or approximately equal to the wavelength of the sound wave.
On the other hand, reflection can be defined as a phenomenon which typically involves a change in the direction of a wave (bounces back) as it falls on a surface.
Hence, reflection is the property of sounds which animals such as bats use to detect their paths as they navigate from one point to another. This phenomenon is generally referred to as echolocation and it typically involves the use of reflection (echo) of sound to gain information about the nature and location of surrounding objects.
A small block is attached to a spring with a spring constant of 85 N/m. When the spring is compressed 0.30 meters and the released, the 0.50 kg block is launched. What is the final speed of the block?
A)
8.42 m/s
B)
3.91 m/s
C)
7.14 m/s
D)
15.3 m/s
Answer:
Explanation:
These Hooke's Law problems are tricky. Here's what we need to know that clears up the problem entirely. The final and also the max speed of the block will be reached at the point where the potential energy of the system is 0. So the equation we need, namely,
[tex]KE+PE=\frac{1}{2}kA^2[/tex] can be simplified down to
[tex]KE=\frac{1}{2}kA^2[/tex] and we solve this first for KE:
[tex]KE=\frac{1}{2}(85)(.30)^2[/tex] and, paying NO attention whatsoever to significant digits here (because if you did the answer you get is not one of the choices)
KE = 3.825 J. Now we can use that value of kinetic energy and solve for the speed we need:
[tex]KE=\frac{1}{2}mv^2[/tex] so
[tex]3.825=\frac{1}{2}(.50)v^2[/tex] so
[tex]v=\sqrt{\frac{2(3.825)}{.50} }[/tex] so
v = 3.91 m/s
what is importance of measurment in our daily life ?
Measurement tools improve the quality and quantity of our lives by making them easier and safer. The ability to precisely quantify physical qualities has arguably enormous survival value, providing humans with an adaptive, evolutionary advantage refined over thousands of years of natural selection.
#CarryOnLearning
help me with the question b.
Answer:
a) The specific heat capacity means the amount of heat needed by a unit mass of a material to increase its temperature in one unit.
b) Liquid P - [tex]Q = 3840\,J[/tex], Liquid Q - [tex]Q = 5500\,J[/tex], Liquid R - [tex]Q = 7800\,J[/tex], Liquid S - [tex]Q = 2856\,J[/tex]
Explanation:
a) The specific heat capacity means the amount of heat needed by a unit mass of a material to increase its temperature in one unit.
b) Let suppose that heat transfer rates between liquids and surroundings are stable. The quantity of the heat released is determined by the following expression:
[tex]Q = m\cdot c\cdot (T_{r} - T_{f})[/tex] (1)
Where:
[tex]m[/tex] - Mass of the liquid, in kilograms.
[tex]c[/tex] - Specific heat capacity, in joules per kilogram-degree Celsius.
[tex]T_{r}[/tex] - Initial temperature of the sample, in degrees Celsius.
[tex]T_{f}[/tex] - Freezing point, in degrees Celsius.
Liquid P ([tex]m = 1\,kg[/tex], [tex]c = 160\,\frac{J}{kg\cdot ^{\circ}C}[/tex], [tex]T_{r} = 30\,^{\circ}C[/tex], [tex]T_{f} = 6\,^{\circ}C[/tex])
[tex]Q = (1\,kg)\cdot \left(160\,\frac{J}{kg\cdot ^{\circ}C} \right)\cdot (30\,^{\circ}C - 6\,^{\circ}C)[/tex]
[tex]Q = 3840\,J[/tex]
Liquid Q ([tex]m = 1\,kg[/tex], [tex]c = 220\,\frac{J}{kg\cdot ^{\circ}C}[/tex], [tex]T_{r} = 30\,^{\circ}C[/tex], [tex]T_{f} = 5\,^{\circ}C[/tex])
[tex]Q = (1\,kg)\cdot \left(220\,\frac{J}{kg\cdot ^{\circ}C} \right)\cdot (30\,^{\circ}C - 5\,^{\circ}C)[/tex]
[tex]Q = 5500\,J[/tex]
Liquid R ([tex]m = 1\,kg[/tex], [tex]c = 300\,\frac{J}{kg\cdot ^{\circ}C}[/tex], [tex]T_{r} = 30\,^{\circ}C[/tex], [tex]T_{f} = 4\,^{\circ}C[/tex])
[tex]Q = (1\,kg)\cdot \left(300\,\frac{J}{kg\cdot ^{\circ}C} \right)\cdot (30\,^{\circ}C - 4\,^{\circ}C)[/tex]
[tex]Q = 7800\,J[/tex]
Liquid S ([tex]m = 1\,kg[/tex], [tex]c = 102\,\frac{J}{kg\cdot ^{\circ}C}[/tex], [tex]T_{r} = 30\,^{\circ}C[/tex], [tex]T_{f} = 2\,^{\circ}C[/tex])
[tex]Q = (1\,kg)\cdot \left(102\,\frac{J}{kg\cdot ^{\circ}C} \right)\cdot (30\,^{\circ}C - 2\,^{\circ}C)[/tex]
[tex]Q = 2856\,J[/tex]
How does an electric bulb work?
this is a class 6 question...
Answer:
Explanation:
When a light bulb connects to an electrical power supply, an electrical current flows from one metal contact to the other. As the current travels through the wires and the filament, the filament heats up to the point where it begins to emit photons, which are small packets of visible light.
the train left weston and arrived at easton 3 hours and 30 minutes later the speed was 104 km per hour what was the total distance covered?
Answer:
104 times by 3.3
Explanation:
104 is the distance for 1 hour. So you need to multiply it by 3.3( because it's 3 hour and 30 minutes)
.If a vehicle covers 3 km in 5 minutes, calculate the speed of the vehicle? (With process )
Answer:
Speed = 1.6 m/s
Explanation:
Formula,
Speed = Distance ÷ Time
list 8 countries which have launched satellites into space and also list the name of the satellite which was launched by the countries
Two parallel circular rings of radius R have their centres in the X axis separated by a distance L. If each ring carries a uniformly distributed charge Q,find the electric field at points along the X axis
Answer:
E" = Q/4πε₀√[(x² + R²)]³(x - (L - x)/√[(L - 2x)L/(x² + R²) + 1]³})
Explanation:
The electric field due to a charged ring of radius R at a distance x from the center of the ring when the axis of the ring is located on the x - axis is
E = Qx/4πε₀[√(x² + R²)]³
Since the rings are separated by a distance L, the electric field at point x due to the second ring is E' = -Q(L - x)/4πε₀[√((L - x)² + R²)]³. It is negative since it points in the negative x - direction.
So, the resultant electric field at x is E" = E + E' = Qx/4πε₀[√(x² + R²)]³ + {-Q(L - x)/4πε₀[√((L - x)² + R²)]³}
E" = Qx/4πε₀√[(x² + R²)]³ - Q(L - x)/4πε₀√[((L - x)² + R²)]³
E" = Q/4πε₀(x/√[(x² + R²)]³ - (L - x)/√[((L - x)² + R²)]³})
E" = Q/4πε₀(x/√[(x² + R²)]³ - (L - x)/√[(L² - 2Lx + x² + R²)]³})
E" = Q/4πε₀(x/√[(x² + R²)]³ - (L - x)/√[(L - 2x)L + (x² + R²)]³})
E" = Q/4πε₀√[(x² + R²)]³(x - (L - x)/√[(L - 2x)L/(x² + R²) + 1]³})
So, the electric field at points along the x axis is
E" = Q/4πε₀√[(x² + R²)]³(x - {(L - x)/√[(L - 2x)L/(x² + R²) + 1]³})
A mobile phone is 35% efficient. Over half an hour 11 kJ of energy is transferred to the phone.
Calculate the amount of energy usefully transferred by the machine over half an hour.
[tex]\\ \sf\longmapsto 35\%\:of 11[/tex]
[tex]\\ \sf\longmapsto 35\%\times 11[/tex]
[tex]\\ \sf\longmapsto \dfrac{35}{100}\times 11[/tex]
[tex]\\ \sf\longmapsto \dfrac{385}{100}[/tex]
[tex]\\ \sf\longmapsto 3.85KJ[/tex]
[tex]\\ \sf\longmapsto 3850J[/tex]
A balloon blown up with air hanging in a room. as the air in the room becomes colder the balloon becomes smaller because the molecules of air become?
I need help answer these questions please
Answer:
1. 25 J
2. 250 J
3. 900,000 J
4. 7,500 J
Explanation:
1. The distance the wheelbarrow is tilted, d = 0.5 m
The force used to tilt the wheelbarrow, F = 50 N
The work done, W = F × d
∴ W = 50 N × 0.5 m = 25 J
2. Work done, W = Force × Distance
The applied force, F = 50 N
The distance the sand is moved, d = 5 m
∴ W = 50 N × 5 m = 250 J
3. The work done, W = The load lifted × The height to which the load is lifted
∴ W = 90,000 N × 10 m = 900,000 J
The work done, W = 900,000 J
4. The work output of the skateboard = The work input × Efficiency
Given that the skateboard is an ideal machine, we have;
The work output of the skateboard = The work input = W
W = F × d
F = 15 N, d = 500 m
∴ W = 15 N × 500 m = 7,500 J
The work output of the skateboard = W = 7,500 J.