When you are driving on the freeway and following the car in front of you, how close is too close? Let's do an estimation.
1. Pick a car model (preferably the one you drive, but can also be any car of your dream), and find its stopping distance at highway speeds (you can usually find this type of data online).
2. Assuming that the car in front of you suddenly does a hard brake. For simplicity, assume that its braking performance is about the same as yours. Then also assume a reasonable amount of reaction time on your part (the time delay between seeing the brake lights lit up and applying your own brake). In order for you not to run into the car your are following, what's the closest distance you need to keep between the two cars?
3. Redo the same calculation if the vehicle in front of you is a typical big-rig truck. Find its braking data online.
4. There is a rule of thumb which says that you must stay one car length behind the car in front of you for every 10 mi/h of driving speed. From your calculation, does this rule make sense?

Answer:

1.matter is any substance that has mass and takes up space by having volume.

2.The three fundamental phases of matter are solid, liquid, and gas (vapour),

3.In gases the particles move rapidly in all directions, frequently colliding with each other and the side of the container. With an increase in temperature, the particles gain kinetic energy and move faster. ... In liquids, particles are quite close together and move with random motion throughout the container.

3.In gases the particles move rapidly in all directions, frequently colliding with each other and the side of the container. With an increase in temperature, the particles gain kinetic energy and move faster. ... In liquids, particles are quite close together and move with random motion throughout the container.

Answer:

the fundamental frequency produced by the open pipe is 120.78 Hz

Explanation:

Given;

length of the open pipe, L = 1.42 m

speed of sound in air, v = 343 m/s

The length of the open pipe for the fundamental frequency is equivalent to half of wavelength;

[tex]L = \frac{\lambda}{2} \\\\\lambda = 2L[/tex]

The fundamental frequency produced by the open pipe is calculated as;

[tex]f_o = \frac{v}{\lambda} \\\\f_o = \frac{v}{2L} \\\\f_o = \frac{343}{2 \times 1.42} \\\\f_o = 120.78 \ Hz[/tex]

Therefore, the fundamental frequency produced by the open pipe is 120.78 Hz

Answer:

Momentum is given by

p

=

m

v

. Impulse is the change of momentum,

I

=

Δ

p

and is also equal to force times time:

I

=

F

t

. Rearranging,

F

=

I

t

=

Δ

p

t

=

0

−

20

,

000

5

=

−

4000

N

.

Explanation:

Momentum before the collision is

p

=

m

v

=

2000

⋅

10

=

20

,

000

k

g

m

s

−

1

.

Assuming the truck comes to a complete halt, the momentum after the collision is

0

k

g

m

s

−

1

.

The change in momentum,

Δ

p

, is initial minus final

→

0

−

20

,

000

=

−

20

,

000

This is called the impulse:

I

=

Δ

p

. Impulse is also equal (check the units) to force times time:

I

=

F

t

.

We can rearrange this expression to make

F

the subject:

F

=

I

t

=

Δ

p

t

=

−

20

,

000

5

=

−

4000

N

The negative sign just means the force acting is in the opposite direction to the initial momentum.

(This will be the average force acting during the collision: collisions are chaotic so the force is unlikely to be constant.)

Answer:

this may be wrong but I am not sure

Answer:

Nuclear power plant.

Gas stove.

Dam.

Gas pump.

Geothermal heat pump.

Power lines.

Solar panels.

Windmills.

Explanation:

Hope this helps :))

Answer:

gasoline,solar panels,geothermal heat pump,windmills

Explanation:

Answer:

stop

Explanation:

object stop

Answer:

If two forces of equal strength act on an object in opposite directions, the forces will cancel, resulting in a net force of zero and no movement. Two or more opposite forces are balanced forces if their effects cancel each other and they do not cause a change in an object's motion.

Answer:

[tex]23796.19\ \text{N}[/tex]

[tex]0.0002032\ \text{s}[/tex]

Explanation:

F = Force

s = Displacement = 6.3 cm

m = Mass of bullet = 7.8 g

v = Velocity of bullet = 620 m/s

t = Time taken

Work done is given by

[tex]W=Fs[/tex]

Kinetic energy is given by

[tex]K=\dfrac{1}{2}mv^2[/tex]

Using work energy considerations we get

[tex]Fs=\dfrac{1}{2}mv^2\\\Rightarrow F=\dfrac{1}{2s}mv^2\\\Rightarrow F=\dfrac{1}{2\times 0.063}\times 7.8\times 10^{-3}\times 620^2\\\Rightarrow F=23796.19\ \text{N}[/tex]

The average force that stops the bullet is [tex]23796.19\ \text{N}[/tex].

Force is given by

[tex]F=m\dfrac{v-u}{t}\\\Rightarrow t=m\dfrac{v-u}{F}\\\Rightarrow t=7.8\times 10^{-3}\times \dfrac{620}{23796.19}\\\Rightarrow t=0.0002032\ \text{s}[/tex]

The time taken to stop the bullet is [tex]0.0002032\ \text{s}[/tex].

Answer:

uADHTiszA?kv

Explanation:

This question is incomplete, the missing image is uploaded along this answer.

Answer:

the coefficient of friction is 0.32

Explanation:

 Given the data in the question;

we make use of kinematic equation of motion;

ω = ω₀ + ∝t

we substitute

ω = ( 0 rad/s ) + ( 0.4 rad/s² )( 9.903 s )

ω = 3.9612 rad/s

The centripetal force acting on the sample is;

Fc = mrω²

from the image; r = 200 mm = 0.2 m

so we substitute

Fc = m(0.2 m ) ( 3.9612 rad/s )²

Fc = (3.13822 m/s²)m

we know that the frictional force between the two materials should be providing the necessary centripetal force to rotate the sample object;

f = Fc

μN = Fc

μmg = (3.13822 m/s²)m

μ = (3.13822 m/s²)m / mg

μ = (3.13822 m/s²) / g

acceleration due to gravity g = 9.8 m/s²

so

μ = (3.13822 m/s²) / 9.8 m/s²

μ = 0.32

Therefore, the coefficient of friction is 0.32

Answer:

If Earth hadn't been hit by Orpheus, it would be covered by ocean, with perhaps a few mountaintops emerging through the water. There would be no humans, but there could be other forms of life. Earth would rotate rapidly, as the moon would not be present to produce the tidal friction that slows Earth's rotation today

Answer:

it is long.

Explanation:

I know the answer but I don't know how to explain it

Answer:

hydrosphere of these Earth spheres interact with oceans during beach erosion.

Answer:

Geosphere

Explanation:

The geosphere is the solid parts of the earth including rocks, minerals, and sand on the beach. The shoreline is where the geosphere meets the ocean. This is how they interact during erosion.

It is not the hydrosphere because the ocean is a part of the hydrosphere.

Answer:

A)

the minimum stopping distance for which the load will not slide forward relative to the truck is 14 m

B)

data that were not necessary to the solution are;

a) mass of truck and b) mass of load

Explanation:

Given that;

mass of load [tex]m_{LS}[/tex] = 10000 kg

mass of flat bed [tex]m_{FB}[/tex] = 20000 kg

initial speed of truck [tex]v_{0}[/tex] = 12 m/s

coefficient of friction between the load sits and flat bed μs = 0.5

A) the minimum stopping distance for which the load will not slide forward relative to the truck.

Now, using the expression

Fs,max = μs [tex]F_{N}[/tex]     -------------let this be equation 1

where [tex]F_{N}[/tex] = normal force = mg

so

Fs,max = μs mg

ma[tex]_{max}[/tex] = μs mg

divide through by mass

a[tex]_{max}[/tex] = μs g    ---------- let this be equation 2

in equation 2, we substitute in our values

a[tex]_{max}[/tex] = 0.5 × 9.8 m/s²

a[tex]_{max}[/tex] = 4.9 m/s²

now, from the third equation of motion

v² = u² + 2as

[tex]v_{f}[/tex]² = [tex]v_{0}[/tex]² + 2aΔx

where [tex]v_{f}[/tex] is final velocity ( 0 m/s )

a is acceleration( - 4.9 m/s² )

so we substitute

(0)² = (12 m/s)² + 2(- 4.9 m/s² )Δx

0 = 144 m²/s² - 9.8 m/s²Δx

9.8 m/s²Δx = 144 m²/s²

Δx = 144 m²/s² /  9.8 m/s²

Δx = 14 m

Therefore, the minimum stopping distance for which the load will not slide forward relative to the truck is 14 m

B) data that were not necessary to the solution are;

a) mass of truck and b) mass of load

Answer:

407.61 seconds

Explanation:

Given that an enormous thunderstorm covers Dallas-Ft. Worth. Your best friend Clark is a storm chaser and heads to the center of the storm to take some readings while you stay dry at home. While Clark is at the center of the storm, he sees and hears lightning strike a tree that is 190 m from where he is standing. You are 140 km from the tree. How long does it take for the sound to reach Clark

Solution.

The distance between the Clark and you will be:

Distance = 140km - 190m

Distance = 140000 - 190

Distance = 139810 m

The radius of the earth is also considered but it will surely be insignificant as you subtracted the two distance values.

Using the formula

Speed = distance/time

Where

The speed of sound = 343 m/s

343 = 139810 / t

Make time the subject of formula

t = 139810 / 343

t = 407.61 s

Therefore, it will take 407.61 seconds for the sound to reach Clark

Answer:

Tangential velocity is the linear speed of any object moving along a circular path

Explanation:

Answer:

Tangential velocity is the linear speed of any object moving along a circular path. A point on the outside edge of a turntable moves a greater distance in one complete rotation than a point near to the center.

Explanation:

i hope this helps and can i get brainliest pls?

The answer is b I just took the test

Neuroticism, psychoticism, and extraversion are the three dominant personality traits according to Hans Eysenck.

Eysenck's theory of personality is based on three logical attributes namely:  

a) Introversion vs. extroversion – Extroversion leads to sociable life , while introversion causes need of being alone and limited interactions

b) Neuroticism vs. stability – Neuroticism leads to anxiousness and an overactive sympathetic nervous system while stability leads to emotional stability.

c) Nsychoticism vs. socialization. - psychoticism  leads to independent thinking, and hostility. While socialization leads to co-operative and conventional behaviour.  

Therefore Neuroticism, psychoticism, and extraversion are the three dominant personality traits according to Hans Eysenck.

To know more about Hans Eysenck's theory follow

https://brainly.com/question/11912668

#SPJ2

Answer: Option b, the final velocity is half of the initial velocity.

Explanation:

Here we will use the conservation of the total momentum of a system.

This means that the total momentum at the beginning must be the same as the final momentum.

Where momentum is:

P = M*v

Initially, we have two cars, both with the same mass M, and only one of them has a velocity v.

Then the initial momentum is:

P = M*v + M*0 = M*v

After the collision, the two cars move together. Then the total mass that is moving is equal to the sum of the masses of the cars, this is 2*M

and we can suppose that the two cars move at a final velocity v'

Then the final momentum is:

P' = (2*M)*v'

Now we use the conservation of momentum, then:

P = P'

M*v = (2*M)*v'

Now we need to solve this for v'

(M*v)/(2*M) = v'

v/2 = v'

This means that the final velocity is half of the initial velocity.

Then the correct option is option b.

Answer:

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Answer:

The ball has a mass of 7/9 kg

Explanation:

Momentum is just mass times velocity, so to find its mass, we can simply divide the given momentum by the given velocity.

[tex]3.5 kg\frac{m}{s} \div 4.5\frac{m}{s} = \frac{7}{9}kg[/tex]

Answer:

20.49 N

Explanation:

From the question given above, the following data were obtained:

Power (P) = 0.824 hp

Velocity (v) = 30 m/s

1 h = 746 W

Force (F) =?

Next, we shall convert 0.824 hp to Watts (W). This can be obtained as follow:

1 h = 746 W

Therefore,

0.824 hp = 0.824 hp × 746 W / 1 h

0.824 hp = 614.704 W

Finally, we shall determine the force as follow:

Power (P) = 614.704 W

Velocity (v) = 30 m/s

Force (F) =?

P = F × v

614.704 = F × 30

Divide both side by 30

F = 614.704 / 30

F = 20.49 N

This question is incomplete, the complete question is;

What is the magnitude of the electric field at the point (8.70i - 9.10j + 7.20k ) m if the electric potential is given by V = 4.30xyz², where V is in volts and x, y  and z are in meters.

Answer:

the magnitude of the electric field is 5648.67 N/C

Explanation:

Given the data in the question;

Suppose electric field at this point is;

E = Exi + Eyj + Ezk

Now, electric field is given by;

E = -dV/dr

so,

Ex = -d( 4.30xyz² )/dx = -4.30yz²

Ey = -d( 4.30xyz² )/dy = -4.30xz²

Ez = -d( 4.30xyz² )/dz = -8.60xyz

so

E = -4.30yz² i  - 4.30xz² j - 8.60xyz k

now, at the point (8.70i - 9.10j + 7.20k )  

E = (-4.30(-9.10)(7.20)²) i  + (-4.30(8.70)(7.20)²) j + (-8.60(8.70)(-9.10)(7.20) k

E =  2028.499 i - 1939.334 j + 4902.206 k

so, Magnitude of electric field will be;

|E| = √( Ex² +  Ey² + Ez² )

we substitute

|E| = √( (2028.499)² +  (-1939.334)² + (4902.206)² )

|E| = √( 31907448.222993 )

|E| = 5648.67 N/C

Therefore, the magnitude of the electric field is 5648.67 N/C

Answer:

"Cannot be determined," if that's an answer choice. It depends on the velocities of both objects, since momentum=mass*velocity.

Explanation:

Answer:

a

Explanation:

angle of incidence equals angle of reflection on flat surface

Answer:

40 degress

Explanation:

Answer:

[tex]31.035^{\circ}[/tex]

Explanation:

x = Displacement in x direction = 5.34 m

t = Time taken to travel the displacement

y = Displacement in y direction = 0

u = Initial velocity of ball = 7.7 m/s

g = Acceleration due to gravity = [tex]9.81\ \text{m/s}^2[/tex]

Displacement in x direction is given by

[tex]x=u\cos\theta t\\\Rightarrow t=\dfrac{5.34}{7.7 \cos\theta}[/tex]

Displacement in y direction is given by

[tex]y=u\sin\theta t-\dfrac{1}{2}gt^2\\\Rightarrow 0=7.7\sin\theta \dfrac{5.34}{7.7\cos\theta}-\dfrac{1}{2}\times 9.81 (\dfrac{5.34}{7.7\cos\theta})^2\\\Rightarrow 0=7.7\sin\theta-4.905\times \dfrac{5.34}{7.7\cos\theta}\\\Rightarrow 0=7.7^2\sin\theta \cos\theta-4.905\times 5.34\\\Rightarrow 0=7.7^2\dfrac{\sin2\theta}{2}-4.905\times 5.34\\\Rightarrow 0=7.7^2\sin2\theta-4.905\times5.34\times 2\\\Rightarrow \sin2\theta=\dfrac{4.905\times 5.34\times 2}{7.7^2}\\\Rightarrow 2\theta=\sin^{-1}\dfrac{4.905\times 5.34\times 2}{7.7^2}[/tex]

[tex]\Rightarrow \theta=\dfrac{62.07}{2}\\\Rightarrow \theta=31.035^{\circ}[/tex]

The angle at which the ball was thrown is [tex]31.035^{\circ}[/tex].

Answer:

B = An 8 kg book at a height of 3 m

Answer:

the magnitude of the electric field intensity is 20 N/C

Explanation:

 Given the data in the question;

mass m = 1 micro gram = 1 × 10⁻⁹ kg

time duration t = 10 sec

distance s = 1 m

the charge on the particle q = 10⁻¹² Coulomb

force applied on a charged particle due to electric field E is;

F = Eq  ------ equ 1

where q is the charge on the particle.

Also, force on a particle with mass m  will be;

F = ma  ------ equ

where a is acceleration

so F = ma = Eq

ma = Eq -------- equ 3

using kinetic equation

Distance = 1/2×at²

where a is acceleration and t is the time period

now lets consider that initial velocity is zero (0)

Here;

1 m = 1/2 × a × ( 10 s )²

1 m = a × 50 s²

a = 1 m / 50 s²

a = 0.02 m/s²

so, from equation 3

ma = Eq

E = ma / q

we substitute

E = (1 × 10⁻⁹ kg × 0.02) / 10⁻¹² Coulomb

E = 2 × 10⁻¹¹ / 10⁻¹²

E = 20 N/C

Therefore, the magnitude of the electric field intensity is 20 N/C

Explanation:

Video games are developed around a structure that is unique from your usual media, where there is a sense purpose in mind when playing a game, as decided by the player, and it allows them to explore creative options in order to solve scenarios, depending on the genre. In the use of phones, internet, or computers, this structure is more rare and diverse from video games, which does not lean more toward a creative purpose to build from. That idea gives people the inspiration and discover skills they never knew they even had.

Answer:

See explanation

Explanation:

a) Formula for the mass of the sample that remains after t years = N= Noe^-kt

Where;

N = mass at time t years

No = mass at time t= 0

k = decay constant

t = time taken

So,

N = 100e^-kt

b) First,

t1/2 = -ln(1/2)/k

t1/2 = 0.693/k

t1/2 = half life of radium-226 =1590 years

1590 = 0.693/k

k = 0.693/1590

k = 4.36 * 10^-4

So,

N= 100e^-(4.36 * 10^-4 * 1000)

N= 65 mg

c) From

N = 100e^-kt

40 = 100e^-(4.36 * 10^-4t)

40/100 = e^-(4.36 * 10^-4t)

0.4 = e^-(4.36 * 10^-4t)

ln(0.4) = ln(e^-(4.36 * 10^-4t))

-0.9163 = -4.36 * 10^-4t

t = 0.9163/4.36 * 10^-4

t = 2102 years

Answer:

D) The buoyant force depends on the volume of the liquid displaced.

Explanation:

Buoyancy can be defined as an upward force which is created by the water displaced by an object.

According to Archimede's principle, it is directly proportional to the amount (weight) of water that is being displaced by an object.

Thus, the greater the amount of water an object displaces; the greater is the force of buoyancy pushing the object up.

The buoyancy of an object is given by the formula;

[tex] Fb = pgV [/tex]

[tex] But, \; V = Ah [/tex]

[tex] Hence, \; Fb = pgAh [/tex]

Where;

The unit of measurement for buoyancy is Newton (N).

Additionally, the density of a fluid is directly proportional to the buoyant force acting on it i.e as the density of a liquid decreases, buoyancy decreases and vice-versa.

Hence, the statement concerning the buoyant force on an object submerged in a liquid which is true is that the buoyant force depends on the volume of the liquid displaced.

If an object is completely submerged, the volume of the object is equal to the volume of liquid displaced.