1 ô tô đang chuyển động với vận tốc 40km/h thì hãm phanh với gia tốc 1m/s bình phương .Tính thời gian xe dừng lại

Answer:

F=65 N

Explanation:

Uniform Acceleration

When an object changes its velocity at the same rate, the acceleration is constant.

The relation between the initial and final speeds is:

\(v_f=v_o+a.t\)

Solving for a:

\(\displaystyle a=\frac{v_f-v_o}{t}\)

Where:

vf  = Final speed

vo = Initial speed

a   = Constant acceleration

t   = Elapsed time

The ball is kicked from rest vo=0 to vf=32.5 m/s in t=0.21 s. Computing the acceleration:

\(\displaystyle a=\frac{32.5-0}{0.21}\)

\(a=154.8\ m/s^2\)

Note: We have shown this result rounded to the nearest tenth, but we kept all the decimals in a scientific calculator for further calculations.

The force needed to accelerate the soccer ball is calculated by:

F = ma

The ball has a mass of m=0.42 kg, thus:

F=0.42*154.8

F=65 N

As mentioned, this result can only be obtained by keeping full precision in the above calculations.

Answer:

Sedentary lifestyle is the lifestyle by which most physical activity is abandoned, performing activities that do not require energy consumption or large muscle movements on a large scale, such as using a computer, driving a car or playing video games.

Today, most young people have gradually turned towards sedentary lifestyles, mainly motivated by the increase in technological availability, and the extensive dependence generated on technology both to communicate with their peers (cell phones, social networks, etc. .) and for leisure time (video games, etc.).

Some ways to promote physical activity in young people and prevent sedentary lifestyle can be to create sports groups, where young people can establish social relationships without depending on networks or technological devices, or establish tasks of physical activity during study or work hours.

Sound waves are a type of mechanical wave that propagate through a medium, typically air but also other materials such as water or solids.

Frequency: the frequency of a sound wave refers to the number of cycles or vibrations it completes per second and is measured in Hertz (Hz).

Amplitude: the amplitude of a sound wave refers to the maximum displacement or intensity of the wave from its equilibrium position. It represents the loudness or volume of the sound, with larger amplitudes corresponding to louder sounds and smaller amplitudes corresponding to softer sounds.

Wavelength: the wavelength of a sound wave is the distance between two consecutive points in the wave that are in phase, such as from one peak to the next or one trough to the next. It is inversely related to the frequency of the wave.

Learn more about sound waves at

https://brainly.com/question/1199084

#SPJ1

The earthquake would occur 13 minutes before 10:05 a.m. which will be at 9.52 am.

The p-waves travel with a constant velocity of 7 km/s

The time can be calculated by using the formula

t = d / v

where

T1 =  10:05 a.m

d is the distance they take to travel from the epicenter

v is the speed of the p-waves

On average, the speed of p-waves is

v = 7 km/s

d = 5600 km (given)

Substituting the values in the formula;

t = d / v

t = 5600 ÷ 7

t = 800 seconds

Converting into minutes,

t = 800 ÷ 60

t = 13.3

≈ 13 mins

T1 -  13 mins = T2

10:05 - 13 mins = 9.52 am

It means the earthquake occurred prior 13 minutes, that is at 9.52 am.

Therefore, the earthquake occurred at 9.52 am.

Learn more about earthquakes from the given link.

https://brainly.com/question/25843505

The instantaneous current at the same moment in the RL circuit can be expressed as I = Imaxsin(150), where Imax represents the maximum current.

1. Given that the instantaneous voltage at a specific moment in the RL circuit is V = Vmaxsin(150).

2. We can express the current at the same moment using Ohm's Law, which states that V = IR, where V is voltage, I is current, and R is resistance.

3. In an RL circuit, the resistance is represented by the symbol R, and it is typically associated with the resistance of the wire or any resistors in the circuit.

4. However, the given equation does not explicitly mention resistance.

5. Since we are considering an RL circuit, it suggests the presence of inductance (L) along with resistance (R).

6. In an RL circuit, the voltage across the inductor (VL) can be expressed as VL = L(di/dt), where L is the inductance and di/dt represents the rate of change of current.

7. At any given instant, the total voltage across the circuit (V) can be expressed as the sum of the voltage across the resistor (VR) and the voltage across the inductor (VL).

8. Therefore, V = VR + VL.

9. Since the given equation represents the instantaneous voltage (V), we can deduce that V = VR.

10. By comparing V = VR with Ohm's Law (V = IR), we can conclude that I = Imaxsin(150), where Imax represents the maximum current.

The specific values of Vmax, Imax, and the phase angle have not been provided in the question, so we are working with the general expression.

For more such questions on current, click on:

https://brainly.com/question/1100341

#SPJ8

The angle of the seal's path below the horizontal at 22.6 degree, cover 991 m distance at the speed 17.53 m/s.

A. We can use the tangent function to find the angle of the seal's path below the horizontal:

tan(angle) = opposite side / adjacent side = 360 m / 920 m = 0.3913

angle = tan^-1(0.3913) = 22.6 degrees below the horizontal

B. To find the total distance covered by the seal, we can use the Pythagorean theorem:

distance = sqrt(360^2 + 920^2) = sqrt(130320 + 846400) = sqrt(976620) = 991 m

C. To find the seal's speed, we divide the total distance covered by the time taken:

speed = distance / time = 991 m / 4.0 min * (1 min / 60 s) = 17.53 m/s.

You can learn more about Pythagorean theorem at

https://brainly.com/question/343682

#SPJ4

Answer:

100Πrad/s

Explanation:

f = 50cycles/sec = 50HZ

w = 2Πf = 2Π(50) = 100Π

w = 100Πrad/s

Hope this helps...

they are formed when hot

it's dependent on the rate of cooling of the melt, slow cooling allows large crystals to form, fast cooling yields small crystals. They cool too quickly to form crystals.

Hope this helps! <3 :3

Answer:

6.601 N/m.

Explanation:

Generally, the force on a wire carrying current in a magnetic field can be determined by:

F = BIL Sinθ

where: F is the force, B is the value of the magnetic field, I is the value of current in the wire and θ is the angle between the direction of current and magnetic field.

For force per meter of length, we have;

\(\frac{F}{L}\) = BI Sinθ

Given: I = 8.05 A, B = 0.82 T and θ = \(90^{o}\)(since they are perpendicular).

Then;

\(\frac{F}{L}\) = 0.82 x 8.05 x Sin \(90^{o}\)

  = 6.601

  = 6.601 N/m

the force per meter length is 6.601 N/m.

The required magnitude of force per meter of wire is of 6.601 N/m.

Given data:

The magnitude of current in a wire is, I = 8.05 A.

The strength of magnetic field is, B = 0.82 T.

We known that, in a magnetic field there is always a force acting on a wire kept in the region. This force is known as magnetic force, and the expression for the magnetic force is given as,

\(F = B \times I \times L \times sin \theta\)

Now,

For the force per unit length, and current being perpendicular to magnetic field,

\(\dfrac{F}{L} = B \times I \times sin90\\\\\dfrac{F}{L} = 0.82 \times 8.05 \times sin90\\\\\dfrac{F}{L} = 6.601 \;\rm N/m\)

Thus, we can conclude that the required magnitude of force per meter of wire is of 6.601 N/m.

Learn more about the magnetic force here:

https://brainly.com/question/9633443

Answer:

1.08 ×10^9 N attraction

Explanation:

By employing Columbs law of force between charge .the force is defined as;

F = KQ1Q2/ r2

= 9×10^9 ×80×40×(6×10^-6) / 0.4 ^2

= 1.08 ×10^9 N

K = 9×10^9 N m2/C2

The object of interest for this situation is the piano. The forces acting on the piano are: (1) gravitational force acting on the piano (piano's weight). (2) force of the floor on the piano (normal force). (3) force of Chadwick on the piano

In this situation, the object of interest is the piano. The forces acting on the piano are the gravitational force (weight) pulling the piano down, the normal force of the floor pushing up on the piano, and the force of Chadwick pushing on the piano to move it up the ramp. Since the ramp is frictionless, the only force acting to stop the piano from sliding back down the ramp is the normal force of the floor, which is perpendicular to the ramp surface. Therefore, Chadwick must push the piano with a force greater than its weight to overcome gravity and move it up the ramp.

Learn more about gravity here: brainly.com/question/4014727

#SPJ4

Complete question:

Chadwick now needs to push the piano up a ramp and into a moving van. The ramp is frictionless. Is Chadwick strong enough to push the piano up the ramp alone or must he get help? To solve this problem you should start by drawing a free-body diagram.

Determine the object of interest for this situation.

Identify the forces acting on the object of interest. From the list below, select the forces that act on the piano.

(1) gravitational force acting on the piano (piano's weight)

(2) force of the floor on the piano (normal force)

(3) force of Chadwick on the piano

Answer:

0.9 kg

Explanation:

We would use the equation F=m*a to solve this equation. First, we would need to get mass by itself therefore we divide out acceleration from both sides ( F/a=m*a / a ) acceleration would cancel out and the end equation should look like this ( F/a = m or m = F/a)  After we do that we plug in the numbers 1.35 N / 1.5 m/s^2 we get 0.9 kg, assuming you are using kg.

Answer: 0.90 kilograms

Explanation:

The mass of the planet is  5.98 × 10^24 kg.

To calculate the mass of the planet, we can use Kepler's Third Law of Planetary Motion. This law states that the square of the period of revolution of a planet around the sun is directly proportional to the cube of the semi-major axis of its orbit.

First, we need to convert the period of the satellite's orbit to seconds. We know that there are 60 minutes in an hour, so the period can be expressed as (6 × 60 + 12) minutes, which equals 372 minutes. Multiplying this by 60 seconds, we get a period of 22,320 seconds.

Next, we need to find the semi-major axis of the orbit. In a circular orbit, the semi-major axis is equal to the radius of the orbit. Therefore, the semi-major axis is 8.8 × 10^6 m.

Now, we can apply Kepler's Third Law to calculate the mass of the planet. The formula is T^2 = (4π^2/GM) × a^3, where T is the period of revolution, G is the gravitational constant, M is the mass of the planet, and a is the semi-major axis of the orbit.

Rearranging the formula, we can solve for the mass of the planet:
M = (4π^2/G) × a^3 / T^2

Plugging in the values, we get:
M = (4 × π^2 / 6.67430 × 10^-11) × (8.8 × 10^6)^3 / (22,320)^2

Evaluating this expression, we find that the mass of the planet is approximately 5.98 × 10^24 kg.

For more such question on mass visit:

https://brainly.com/question/24191825

#SPJ8

To calculate the volume of a parallelepiped given the sides, we can use the scalar triple product. The formula for the volume of a parallelepiped with sides a, b, and c is:

Volume = |a · (b × c)|

where · represents the dot product and × represents the cross product.

Using the given sides:

a = (7, 2, 4)

b = (4, 7, 6)

c = (3, 4, 7)

First, calculate the cross product of b and c:

b × c = (7*7 - 4*4, 6*3 - 7*7, 4*4 - 2*3)

      = (49 - 16, 18 - 49, 16 - 6)

      = (33, -31, 10)

Next, calculate the dot product of a and the cross product (b × c):

a · (b × c) = 7*33 + 2*(-31) + 4*10

           = 231 - 62 + 40

           = 209

Finally, take the absolute value of the result to obtain the volume:

Volume = |209| = 209 cubic units

Therefore, the correct answer is:

209 cubic units

The most likely true statement about asynchronous communication is that it is helpful when employees work across multiple time zones.

Asynchronous communication refers to a mode of communication where participants do not need to be present or engaged simultaneously. Instead, they can send and receive messages at their convenience.In today's globalized society, businesses often have teams distributed across different geographical locations and time zones. Asynchronous communication becomes invaluable in such scenarios as it allows team members to collaborate effectively without the constraints of real-time interactions. By utilizing tools like email, project management platforms, or messaging apps, individuals can communicate and exchange information regardless of their location or the time differences.

Asynchronous communication also offers benefits such as flexibility and increased productivity. Team members have the freedom to work at their own pace and prioritize tasks accordingly. It provides opportunities for thoughtful and well-crafted responses, as individuals can take time to gather information or reflect on complex matters before replying.While asynchronous communication is advantageous for teams operating across multiple time zones, it does not rely on all employees working in the same time zone. In fact, it is designed to accommodate diverse schedules and allow individuals to collaborate efficiently despite their varying work hours.

for such more questions on time

https://brainly.com/question/4931057

#SPJ8

The ways to solve this problem is through knowledge dissemination, citizens who were outraged by the article about the negative statements and malicious stories about Filipinos, could submit positive articles about the culture of the Filipino people.

Another way could be through open dialogue, with Filipino internet users, publicly apologizing seeking to become more involved with the Filipino community.

Therefore, the best way to solve the problem is through ethically-based freedom of expression, avoiding stereotypes of a culture you don't belong to, and looking for a way to disseminate respectful and empathetic information about a people.

Learn more here:

https://brainly.com/question/19561423

Answer:

c

Explanation:

Answer:

a protective and waxy or hard layer covering the epidermis of a plant, invertebrate, or shell.

Answer:

The cuticles for animals are a thin layer of clear dead skin around the nail bed on fingers and toes. As the nail grows, it naturally pushes and damages the underside of the skin around the base of the nails, called the eponychium. The space between the eponychium and the bottom of the nail is where the cuticle is located.  

The cuticle definition related to plants is a protective and waxy or hard layer covering the epidermis. The plant cuticle is an extracellular hydrophobic layer that covers the aerial epidermis.

Explanation:

The kinetic energy of the roller coaster at the bottom of the hill is 12250000 J

To answer this question, we must understand that the energy of a system is always conserved as explained by the law of conservation of energy.

The kinetic energy of the roller coaster will be equivalent to the potential energy of the roller coaster.

The kinetic energy of the roller coaster can be obtained as follow:

Kinetic energy = Potential energy

KE = mgh

KE = 2500 × 9.8 × 500

KE = 12250000 J

Therefore, the kinetic energy of the roller coaster is 12250000 J

Learn more about kinetic energy: https://brainly.com/question/14449170

Answer:

range selection lock feature

Explanation:

This feature locks  the meter at a particular range. The range selection lock defeats the

meter’s normal autoranging function, which can become confused if

electrical noise or other signal pulses are present on nearby circuits or

conductors.

Range selection lock feature is  used to override or defeat the autoranging function on a Digital Multimeter (DMM).

Instruments called digital multimeters are used to measure things like voltage, current, and resistance. Digital displays make it possible for even novice users to read measured values quickly and easily.

Some digital multimeters automatically choose the measurement range, removing the need for manual selection. As a result, even for beginners, these instruments are rather simple to use. Naturally, analogue testers have advantages as well. For instance, it is simple to read variations in the measured value during measurement, and a needle may be seen intuitively in places where a digital reading might be challenging to notice.

Learn more about  Digital Multimeter here:

https://brainly.com/question/5135212

#SPJ2

Answer:

F = 233.52 N,  θ' = 351.41º

Explanation:

In this exercise we must find the net force applied on the donkey.

For this we use Newton's second law, where we create a reference frame with the horizontal x axis

let's decompose the forces

Jack

        = 80.5 N

Jill

       cos 45 = F_{2x} / F₂2

       sin 45 = F_{2y} / F₂2

       F_{2x} = F₂ cos 45

       F_{2y} = F₂ sin 45

       F_{2x} = 81.7 cos 45 = 57.77 N

       F_{2y} = 81.7 sin 45 = 57.77 N

Jane

      cos (270 + 45) = F_{3x} / F₃3

      sin 315 = F_{3y} / F₃

      F_{3x} = 131 cos 315 = 92.63 N

      F_{3y} = 131 sin 315 = -92.63 N

the force can be found in each axis

X axis

         F_{x} = F_{1x} + F_{2x} + F_{3x}

         F_{x} = 80.5 +57.77 + 92.63

         F_{x} = 230.9 N

Axis y

         F_{y} = F_{1y} + F_{2y} + F_{3y}

         F_{y} = 0 + 57.77 -92.63

         F_{y} = -34.86 N

we can give the result in two ways

a) F = (230.9 i ^ - 34.86 j ^) N

b) in the form of module and angle

we use the Pythagorean theorem

         F = √(Fₓ² + F_{y}²

        F = √(230.9² + 34.86²)

        F = 233.52 N

let's use trigonometry for the angle

        tan θ = \(\frac{F_y}{F_x} }\)

        θ = tan⁻¹ (\frac{F_y}{F_x} })

        θ = tan⁻¹ (-34.86 / 230.9)

        θ = -8.59º

if we measure this angle from the positive side of the x-axis counterclockwise

          θ' = 360 -θ

          θ‘= 360- 8.59

          θ' = 351.41º

The final velocity of the car can be calculated using the formula: final velocity = initial velocity + acceleration * time. Plugging in the values you provided, we get: final velocity = 5.82 m/s + 2.35 m/s² * 3.25 s = 13.44 m/s.

Answer:

I believe the answer is Mendeleev

Because the cable was not connected properly is the most likely cause of the experiment's failure.

The coils of wire that make up an electromagnet have electricity running through them. When an electric current flows through the wire coils of an electromagnet, the coils act like a magnet because moving charges produce magnetic fields.

There are numerous factors to examine. Make sure an ordinary magnet can attract safety pins as a start. Then, verify that current is actually flowing through your wire. To do this, you need a strong enough battery, a wire with a low enough resistance, and a complete circuit connecting the two.

To learn more about electromagnet visit:

brainly.com/question/3427992

#SPJ1

When mass grows and distance contracts, gravity increases. Additionally, as distance and mass decrease, gravity also reduces.

Manning's universal law of gravity asserts that every atom in the cosmos pulls more or less every particle with a pressure along a connecting line, to put it in modern terms. The force is equal to the ratio of the wavelength between them and found to be proportional to the combination of their masses.

What exactly does the Law of Gravitation apply to  According to Newton's theory of Universal Gravitation, every particle in the cosmos is drawn to every other particle with a force that is equal to the product of their masses and inversely to their distance from one another.

To know more about gravity visit :

https://brainly.com/question/14874038

#SPJ4

When mass grows and distance contracts, gravity increases. Additionally, as distance and mass decrease, gravity also reduces.

Manning's universal law of gravity asserts that every atom in the cosmos pulls more or less every particle with a pressure along a connecting line, to put it in modern terms. The force is equal to the ratio of the wavelength between them and found to be proportional to the combination of their masses.

What exactly does the Law of Gravitation apply to  According to Newton's theory of Universal Gravitation, every particle in the cosmos is drawn to every other particle with a force that is equal to the product of their masses and inversely to their distance from one another.

To know more about gravity visit :

brainly.com/question/14874038

#SPJ1

The distance is 1600 km, and the plane's average speed is x km/hr. The Ordinary aeroplane speed is 800 km/hr.

The distance is 1600 km, and the plane's average speed is x km/hr. The time it takes the plane to fly 1600 km at its current speed is =

Time consumed by the plane at the increased speed is equal to x+400 /1600 km/hr because all time is measured in hours, which must be converted to minutes using the formula 60 /40 hr= 3 2 hr.

Considering the query,/x/ 1600  − x+400 /1600  = 3 /2

⇒ 1600[ x(x+400) x+400−x  ]= 3/ 2

⇒ x(x+400)/ 400 = 3 /2  × 1600/ 1

⇒ x(x+400)= 2400×3×1600

​⇒ x 2 +400x=960000 ⇒ x 2  +400x−960000=0

⇒ x2 +1200x−800x−960000=0

⇒ x(x+1200)−800)x+1200)=0

⇒ (x+1200)(x−800)=0

∴ x=−1200 or x=800

Given that speed cannot be negative.

∴ Ordinary aeroplane speed is 800 km/hr.

The Complete Question is aeroplane speed.

To Learn more About aeroplane speed refer to:

https://brainly.com/question/24208048

#SPJ1

Answer:

6.50m

Explanation:

Vf=0

Vi=11.4

g=-10(against the gravity)

D=x?

Vf²=vi²+2ad

0²=11.4²+2(-10)d

0=129.96+-20d

-129.96=-20d

-129.96/-20=d

D=6.50m

The momentum of an object is the product of its mass and velocity. Among the given objects the 950 kg Chevrolet minivan moving at 18 m/s has the greatest momentum.

Momentum of n object is the product of its mass and velocity. Hence, an increase in the mass or velocity or in both will increase the momentum of the object.

Momentum = mass × velocity

hence the 3000 kg truck stopped in the traffic has no momentum because it has no velocity.

Momentum of 950 kg Chevrolet minivan moving at 18 m/s is:

950 kg × 18 m/s = 17100 kg m/s.

Momentum of 0.040  kg bullet traveling  at 120m/s is:

0.04 kg × 120 m/s = 4.8 kg m/s.

Momentum of 52 kg figure skater gliding at 7 m/s is:

52  kg × 7 m/s = 364  kg m/s.

Therefore, the Momentum of 950 kg Chevrolet minivan moving at 18 m/s has the greatest momentum.

Find more on momentum:

https://brainly.com/question/30677308

#SPJ9