Answer:
C
Explanation:
Seat belts absorb kinetic energy when a car crashes because it pulls you back from falling forward given the kinetic energy (and momentum) you had before the crash.
Air bags absorb kinetic energy when a car crashes because it pushes you back from falling forward given the kinetic energy (and momentum) you had before the crash.
Crumple zones absorb kinetic energy when a car crashes because it provides a cushion when the cars crash. Kind of like dropping your phone into a pillow.
I hope this helps! :)
Answer:
C. Seat belts, crumple zones and air bags
Explanation:
All of these car safety features absorb kinetic energy, including seat belts, crumple zones and air bags.
Select all the correct answers. Which statements about potential energy are true?
Answer: The statement gaining potential energy is always associated with a force field, is true about potential energy.
Explanation:
The energy acquired by an object due to its position is called potential energy.
Basically, a force field exerts a force that gives rise to potential energy of an object. For example, gravity, spring force etc.
This means that gaining potential energy is always associated with a force field.
A change in position does not always means that an object gains potential energy. For example, a spring will have more potential energy when it is compressed or stretched.
Hence, change in position of an object not necessarily means always gain in potential energy.
There are two types of potential energy that is, gravitational potential energy and elastic potential energy.
Thus, we can conclude that the statement gaining potential energy is always associated with a force field, is true about potential energy.
Answer:
Explanation:
The first one and the last one are the correct answer.
a hotgas is injected into at engine at 573 k and exhausts at 343 k. what is the highest efficiency of thisengine?
Answer:
230k
Explanation:
energy capacity maximum is 573 total available. 343k of that energy is present at release and subsequent loss leaving max used energy of 230k.
what is unit of pressure?why is it called a derived unit ? give reasons
Answer:
Unit of pressure is pascal (Pa)
The SI-derived unit of measurement for pressure. The pascal is one newton (an SI-derived unit itself) per square meter.
PLS HELPP HURRYYY
The trapdoor swings open and the ball falls to the ground. The ball does not bounce when it hits the ground. Show that the final speed of the ball at the instant before it hits the ground is about 5 m/s.
Answer:
5 m/s
Explanation:
As the ball falls to the ground, it is acted upon by a force which is due to the gravitational force. Hence, the ball falls with an acceleration called the acceleration due to gravity.
Let us assume that the acceleration due to gravity (g) = 10 m/s², Since initially, the body was at rest, hence the initial velocity (u) = 0 m/s. The height to the ground (h) = 1.3 m. Hence using the equation of motion, the final velocity (v) is:
v² = u² + 2gh
Substituting:
v² = 0² + 2(10)(1.3)
v² = 26
v = √26 = 5
v = 5 m/s
6. Which of the following graphs correctly demonstrates the relationship between the
electromagnetic force and distance between charges?
Answer:
But where are the graphs
Coulomb's Law describes the relationship between electromagnetic force and the distance between charges.
What is the relationship between electromagnetic force and the distance between charges?The relationship between electromagnetic force and the distance between charges is described by Coulomb's Law, which states that the force between two charges is directly proportional to the product of the charges and inversely proportional to the square of the distance between them. Mathematically, Coulomb's Law is expressed as:
F = k (q₁x q₂) / r²
where F is the electromagnetic force, q1 and q2 are the charges, r is the distance between the charges, and k is the Coulomb constant.
This means that as the distance between two charges increases, the force between them decreases, and as the distance decreases, the force increases. The relationship between force and distance is inverse square, which means that the force decreases rapidly as the distance increases.
To know more about electric charges follow
https://brainly.com/question/874116
#SPJ6
A 91.5 kg football player running
east at 2.73 m/s tackles a 63.5 kg
player running west at 3.09 m/s.
What is their velocity afterward?
Answer:
I'm pretty sure the velocity is 2.88 m/s
Explanation:
hope this is right good luck
Answer:
0.348
Explanation:
Acellus
Find the force due to a current element of length 6cm and flux density of 12 tesla. The current through the element will be 10A.
Answer:
7.2 N
Explanation:
Applying,
F = BIL................. Equation 1
Where F = Force due to current through the element, B = magnetic field, L = Length of the element.
From the question,
Given: B = 12 Tesla, L = 6 cm = 0.06 m, I = 10 A
Substitute these values into equation 1
F = 12(0.06)(10)
F = 7.2 N
Hence the force through the element is 7.2 N
Calculate the momentum of a 4,800 kg car with a velocity of 25 m/s.
Answer:
p = 120000 kg · m/s
Explanation:
p = mv
p=momentum
m=mass
v=velocity
p = (4800)(25)
p= 120000 kg · m/s
Answer:
[tex]momentum = mass \times velocity \\ = 4800 \times 25 \\ = 120000 \: kgm {s}^{ - 1} [/tex]
I need help pleaseee
Answer:
a refraction
b reflection
creflection
d refraction
brainliest plzz
A capacitor with a capacitance of 50µf when connected to a battery of 400 V. The charge and energy stored on it is? a. 0.05 C and 5 J b. 0.05 C and 10 J c. 0.02 C and 4 J d. 0.08 C and 12 J
Answer:
c. 0.02 C and 4 J
Explanation:
Applying,
Q = CV................ Equation 1
Where Q = Charge, C = Capacitance of the capacitor, V = Voltage.
From the question,
Given: C = 50 μF = 50×10⁻⁶ F, V = 400 V
Substitute these values into equation 1
Q = (50×10⁻⁶)(400)
Q = 0.02 C.
Also Applying
E = CV²/2............. Equation 2
Where E = Energy stored.
Therefore,
E = (50×10⁻⁶ )(400²)/2
E = 4 J
Hence the right option is c. 0.02 C and 4 J
Which of the motion variables is the same in both thex and y axis?
A) velocity
B) acceleration
C) time
D) displacement
Answer:
Acceleration (b) not sure tho
Explanation:
Which property of the coating on fiber-optic strands makes light visible only at the ends of the strands?
reflectivity
absorbency
transparency
translucency
The answer is A, Hope this helps and sorry for being late :)
A 8.6*10^ -6 C charge is places 1.00 m away from a 2.3 * 10 ^ - 4 * C charge. How large is the force of repulsion between the two charges?
Answer:
The force of repulsion is 17.802 N
Explanation:
Given;
magnitude of the first charge, q₁ = 8.6 x 10⁻⁶ C
magnitude of the second charge, q₂ = 2.3 x 10⁻⁴ C
distance between the two charges, r = 1 m
The force of repulsion is calculated using Coulomb's law;
[tex]F = \frac{Kq_1q_2}{r^2} \\\\F = \frac{9\times 10^9 \times 8.6\times 10^{-6} \times 2.3\times 10^{-4}}{1^2} \\\\F = 17.802 \ N[/tex]
Therefore, the force of repulsion is 17.802 N
Sound travels slowest through gases _____________________. Group of answer choices because the molecules of gas are close together because gases are air because the molecules of gas are far apart because gases have the lowest temperature
A _____ is a model of an atom in which each dot represents a valence electron
Answer:
electron dot diagram is the answer to your question.
A body at rest or moving with uniform velocity will have acceleration equals
to:
A.
1
B.
0
C.
Negligible
D.
Infinity
Answer:
B:O
Explanation:
As acceleration is the rate of change of velocity with time, if velocity is uniform, there will be no change in it and acceleration will be zero.
how can you reduce output voltage to 6v in transformers if the input voltage is 240v
Answer:
[tex]N_P = 40\ N_S[/tex]
To reduce the output voltage to 6v in transformers if the input voltage is 240v, we need to have 40 times as many turns in the primary coil as there are in the secondary coil.
Explanation:
The change in voltage of a transformer depends upon the turns ratio of the transformer between secondary and primary coil. Following formula can be used to determine the turns ratio in this case:
[tex]\frac{N_P}{N_S} = \frac{V_P}{V_S} \\\\[/tex]
where,
[tex]N_P[/tex] = No. of turns in the primary coil
[tex]N_S[/tex] = No. of turns in the secondary coil
[tex]V_P[/tex] = voltage in the primary coil = 240 V
[tex]V_S[/tex] = voltage in the secondary coil = 6 V
Therefore,
[tex]\frac{N_P}{N_S} = \frac{240\ V}{6\ V} \\\\N_P = 40\ N_S[/tex]
To reduce the output voltage to 6v in transformers if the input voltage is 240v, we need to have 40 times as many turns in the primary coil as there are in the secondary coil.
The atomic mass of calcium is 40.08. What is the mass of 6.02 × 1023 atoms of calcium?
Answer:
It is 40.08 g
Explanation:
[tex]6.02 \times 10 {}^{23} \: atoms = 1 \: mole = 40.08 \: g[/tex]
Henry mixed salt and water together in a cup until he observed a clear solution. He measured the mass of the solution. Then he placed the cup outside for several sunny days during the summer. After a week, he observed that only solid salt remained in the cup and the mass had decreased. Henry concluded that a physical and chemical change occurred in this investigation.
Which statements correctly defend or dispute his conclusion?
He is correct. Dissolving salt in water is a physical change, but evaporating the water is a chemical change. Formation of a solid is evidence that a chemical change occurred.
He is correct. Evaporation is a physical change, but dissolving salt in water is a chemical change. The change in mass is evidence that a chemical change occurred.
He is incorrect. Dissolving salt in water and evaporation of the water are both physical changes. The reappearance of salt is evidence that the change was reversible by a physical change, so it could not be a chemical change.
He is incorrect. Dissolving salt in water and evaporation of the water are both chemical
Answer:
He is incorrect. Dissolving salt in water and evaporation of the water are both physical changes. The reappearance of salt is evidence that the change was reversible by a physical change, so it could not be a chemical change.
Answer:c
Explanation:
According to the theory of plate tectonics, the lithosphere is separated into sections that are called tectonic plates. These plates move in different directions in response to the forces in Earth’s mantle beneath them. Which of the following correctly matches the plate movement with its description?
convergent boundary; plates move away from one another causing rift valleys and the formation of new crustal material
transform boundary; plates slide past one another in opposite directions causing the formation of faults and earthquakes
divergent boundary; as the plates come together gravity pushes the edge of one plate underneath the edge of a neighboring plate
subduction zone; as the plates come together increased pressure causes the plates to fault and fracture leading to the formation of mountains
Answer:
The correct answer is - transform boundary; plates slide past one another in opposite directions causing the formation of faults and earthquakes.
Explanation:
If the continental or oceanic plates slide past one another either in the same direction or in opposition direction forms the transform fault boundary. Due to this tectonic plate formation, no new crust is formed or subducted, but earthquake activities forms.
Convergent boundaries forms by pushing the edge of one plate underneath the other while coming together whereas plates move away from one another causing rift valleys called divergent boundary.
6. A ball rolled 125 m from the top of a hill to the bottom of a hill. How long
did it take for the ball to roll if the average velocity was 5m/s? *
The total momentum before a collision is___to the total momentum after a collision
Answer:
Equal
Explanation:
The law of conservation of energy states that the total momentum before and after a collision are equal
Answer:
Equal to the total momentum of the two objects after the collision.
1. 10. waves break on the beach in 2.0 min. What is the frequency in hertz of these waves (cycles per
second)? What is the time between successive waves, in seconds?
Answer:
there it is fella tried o. ma own consciousness
Si un automóvil logra una potencia util promedio de 250kw y se sabe que tiene un rendimiento energético del 25%. ¿Cuanta energia total consume en 1 min? Exprese el resultado en kj
Answer:
W = 3.75 kJ
Explanation:
Power is defined by the relational
P = W / t
W = P t
the yield is 25% = 0.25
W = 0.25 Wo
W = 0.25 250 60
W = 3750 J
W = 3.75 kJ
the refractive index of rock salt with respect to water is 1.17. What will be the refractive index of water with respect to rock salt
Answer:
1.17
Explanation:
Given that,
The refractive index of rock salt with respect to water is 1.17.
We need to find the refractive index of water with respect to rock salt.
We know that,
Refractive index = (speed of light in air or vaccum)/( speed of light in that medium)
Refractive index of rock salt with respect to ice = (speed of light in ice)/(speed of light in rock salt)
The speed of light in ice = c/1.31
The speed of light in rock salt = c/1.54
Required refractive index,
[tex]\mu=\dfrac{1.54}{1.31}\\\\=1.17[/tex]
So, the refractive index of water with respect to rock salt is equal to 1.17.
I will be so thankful if u answer correctly!!
(a) 10N
Explanation:The sketch of the two cases has been attached to this response.
Case 1: The box is pushed by a horizontal force F making it to move with constant velocity.
In this case, a frictional force [tex]F_{r}[/tex] is opposing the movement of the box. As shown in the diagram, it can be deduced from Newton's law of motion that;
∑F = ma -------------------(i)
Where;
∑F = effective force acting on the object (box)
m = mass of the object
a = acceleration of the object
∑F = F - [tex]F_{r}[/tex]
m = 50kg
a = 0 [At constant velocity, acceleration is zero]
Substitute these values into equation (i) as follows;
F - [tex]F_{r}[/tex] = m x a
F - [tex]F_{r}[/tex] = 50 x 0
F - [tex]F_{r}[/tex] = 0
F = [tex]F_{r}[/tex] -------------------(ii)
Case 2: The box is pushed by a horizontal force 1.5F making it to move with a constant velocity of 0.1m/s²
In this case, the same frictional force [tex]F_{r}[/tex] is opposing the movement of the box.
∑F = 1.5F - [tex]F_{r}[/tex]
m = 50kg
a = 0.1m/s²
Substitute these values into equation (i) as follows;
1.5F - [tex]F_{r}[/tex] = m x a
1.5F - [tex]F_{r}[/tex] = 50 x 0.1
1.5F - [tex]F_{r}[/tex] = 5 ---------------------(iii)
Substitute [tex]F_{r}[/tex] = F from equation (ii) into equation (iii) as follows;
1.5F - F = 5
0.5F = 5
F = 5 / 0.5
F = 10N
Therefore, the value of F is 10N
give reason for the following observation
The smell of hot sizzling food reaches you several metres away but to get the smell from cold food you have to go close.
Answer: The smell of hot sizzling food reaches you several metres away, but to get the smell from cold food you have to go close because the kinetic energy of the particles of matter increases with the increase in temperature. In cold foods, kinetic energy is less while in hot foods, kinetic energy is more
hope this helps
Smell spreads due to diffusion. In hot food the molecules have a lot of kinetic energy , and they therefore spread fast , whereas in cold food the kinetic energy of the molecules are less and they don't spread far.
find out the speed of the car from home to school in meters per second.
Time - 15 mins
Distance - 8 km
1.875
Explanation:
speed = distance moved ÷ time taken
A scientist is examining an unknown solid. Which procedure would most likely help determine a chemical property of the substance?
heating it to find the temperature at which it melts
exposing it to a flame to see if it catches on fire
hitting it with a hammer to determine if it breaks or bends
placing it in water to find out whether or not it dissolves
Answer:
hitting it with a hammer to determine if it breaks or bends
Answer:
exposing it to a flame to see if it catches on fire
Explanation:
A chemical property is when the matter changes into a different substance. This is true when you expose it to a flame because if a substance is burned, it will change into a new substance. All the other options are examples of physical changes.
-I also took the quiz and got 100%
Hope this helps!
What the answer to the three of them ill mark brainlest
lhormmia masng ies igentetel
Explanation:
