Which is the BEST example of selective attention?

Answer:

K.E₂ = mg(h - 2R)

Explanation:

The diagram of the car at the top of the loop is given below. Considering the initial position of the car and the final position as the top of the loop. We apply law of conservation of energy:

K.E₁ + P.E₁ = K.E₂ + P.E₂

where,

K.E₁ = Initial Kinetic Energy = (1/2)mv² = (1/2)m(0 m/s)² = 0 (car initially at rest)

P.E₁ = Initial Potential Energy = mgh

K.E₂ = Final Kinetic Energy at the top of the loop = ?

P.E₂ = Final Potential Energy = mg(2R) (since, the height at top of loop is 2R)

Therefore,

0 + mgh = K.E₂ + mg(2R)

K.E₂ = mg(h - 2R)

The kinetic energy of the car is expressed as K.E = mg(h - 2R). The energy of the object by the integrity of its movement is understood as kinetic energy.

The energy of the body by the virtue of its motion is known as the kinetic energy of the body. It is defined as the product of half of mass and square of velocity.

The following data is observed from the figure;

K.E₁ = Initial Kinetic Energy = (1/2)mv² = (1/2)m(0 m/s)² = 0

P.E₁ = Initial Potential Energy = mgh

K.E₂ = Final Kinetic Energy at the top of the loop =?

P.E₂ = Final Potential Energy = mg(2R) (since, the height at top of loop is 2R)

According to the law of conservation of energy, total energy is defined as the sum of kinetic energy and potential energy.

Total energy = kinetic energy+potential energy

On applying the law  of conservation of energy for top and bottom of the loop;

K.E₁ + P.E₁ = K.E₂ + P.E₂

0 + mgh = K.E₂ + mg(2R)

K.E₂ = mg(h - 2R)

Hence the kinetic energy of the car is expressed as K.E = mg(h - 2R).

To learn more about kinetic energy refer to the link;

brainly.com/question/999862

Answer:

599.245km/hr

Explanation:

A plane is heading due west and climbing at the rate of 80 km/hr. If its airspeed is 540 km/hr and there is a wind blowing 80 km/hr to the northwest, what is the ground speed of the plane?

We solve the above question using vectors

In vector form Air speed is -540i + 0j Wind speed is (-80/√2)i + (80/√2)j

Vector notation wind speed is given as: -56.5685 i + 56.5685j

The vector for the ground speed of the plane =

-540i + 0j -56.5685i + 56.5685j

= -596.56854249i + 56.5685j

The the ground speed of the plane √[(596.56854249)² + (56.5685)²]

= √359094.021081 km/hr

= 599.24454197 km/hr

Approximately

= 599.245km/hr

Answer:

22 m/s

Explanation:

PEf +KEf =PE0 +KE0 →PE0 −PEf =KEf

−mgΔy= 1 mv2 →v= −2gΔy = −2(9.8 m/s2)(−25 m)=22 m/s

Answer:

jus multiply by 69

Explanation:

5 * 10² m

We are Given:

Frequency of the wave = 6 * 10⁵ Hz

Wavelength of the wave:

We know the relation:

c = λν  

[where λ (Lambda) is the wavelength ,ν (nu) is the frequency and c is the speed of light ]

3 * 10⁸  m/s= (6 * 10⁵ )* λ                          [replacing known values]

λ = [tex]\frac{3 * 10^{8}}{6 * 10^{5}}[/tex]                                                     [dividing both sides by 6 * 10⁵]

λ = 1/2 * 10³  

λ = 1/2 * 10 * 10²                                        [10³ can be rewritten as 10 * 10²]

λ = 5 * 10² m

Therefore, the wavelength of the wave is 5 * 10² m

Answer:

Option (a) is correct.

Explanation:

Given that,

The radius of a circular disk, r = 2 m

Angular acceleration, [tex]\alpha =2\ rad/s^2[/tex]

We need to find the tangential acceleration of a point on the edge of the disk at the instant that its angular speed is 1.0 rev/s.

Let a is the tangential acceleration. The relation between the angular acceleration and tengential acceleration. Let it is a.

[tex]a=\alpha r\\\\a=20\times 2\\\\a=40\ m/s^2[/tex]

So, the tangential acceleration is [tex]40\ m/s^2[/tex].

Answer:

[tex]\boxed {\boxed {\sf v= 4.5 \ m/s}}[/tex]

Explanation:

The formula for momentum is:

[tex]p=mv[/tex]

(p is momentum, m is mass, and v is velocity)

Let's rearrange the formula for velocity, or v.

[tex]\frac{p}{m} =v[/tex]

Velocity can be found by dividing the momentum by the mass.

The momentum is 180 kilograms meter per second. The mass of the boy is 40 kilograms.

[tex]p=180 \ kg*m/s \\m=40 kg[/tex]

Substitute the values into the formula.

[tex]v=\frac{180 \ kg*m/s}{40 \ kg}[/tex]

Divide. Note that the kilograms or "kg" will cancel each other out.

[tex]v=\frac{180 \ m/s}{40 }[/tex]

[tex]v= 4.5 \ m/s[/tex]

The velocity of the boy is 4.5 meters per second.

Answer:20cm

Explanation:

Answer:

10 m/s²

Explanation:

The above question simply indicates motion under gravity.

The acceleration due to gravity (i.e acceleration of free fall) has a constant value of 10 m/s².

Whether the rock is dropped from a height of 5 m or 2.5 m, it will accelerate at 10 m/s² before striking the ground. The only thing that will be different is the time taken for the rock to strike the ground when released from both 5 m and 2.5 m.

Thus, the rock will have a constant acceleration of 10 m/s² irrespective of the height to which it was released.

Since acceleration due to gravity is a constant,  the acceleration of the rock dropped from the 5 m height is the same as that dropped from the 2.5 m height and is equal to 10 m/s²

Acceleration due to gravity is the acceleration a body falling freely from a height above the earth surface which a body experiences due to the gravitational force of attraction of the earth on the body.

Acceleration due to gravity has a constant value which is equal to 10 m/s².

Therefore, the acceleration of the rock dropped from the 5 m height is the same as that dropped from the 2.5 m height and is equal to 10 m/s².

Learn more about acceleration due to gravity at: https://brainly.com/question/11873969

Answer:

The value of acceleration that accomplishes this is 8.61 ft/s² .

Explanation:

Given;

maximum distance to be traveled by the car when the brake is applied, d = 450 ft

initial velocity of the car, u = 60 mph = (1.467 x 60) = 88.02 ft/s

final velocity of the car when it stops, v = 0

Apply the following kinematic equation to solve for the deceleration of the car.

v² = u² + 2as

0 = 88.02² + (2 x 450)a

-900a = 7747.5204

a = -7747.5204 / 900

a = -8.61 ft/s²

|a| = 8.61 ft/s²

Therefore, the value of acceleration that accomplishes this is 8.61 ft/s² .

Answer:

They both pull the same amount. For every force there is an equal and opposite force.

Explanation:

Answer:

B

Explanation:

[tex]\huge\boxed{False}[/tex]

Endothermic Reaction are those reactions in which the reactants absorb the energy from their surrounding and forms the product.

Those changes in which a substance goes from More-ordered state to less-oredered state are endothermic. Where they change from less ordered to more ordered is exothermic.

More ordered means that the movement of vibration of the particles of the substance is less and the are more close to each other. More to less ordered state is given as,

Solid>Liquid>Gas.

In the question it asks about the melting of the ice cube. Ice cube is a solid, and when it will melt, it will change into the liquid water. As we know that, Solid is more ordered and Liquid is less ordered, and The change from more-ordered to less-ordered is endothermic thus the answer is ENDOTHERMIC.

Answer:

The final velocity of the car is 16.893 m/s

The final velocity of the truck is 4.393 m/s

Explanation:

Given;

mass of the car, m₁ = 715 kg

mass of the truck, m₂ = 1490 kg

initial velocity of the car, u₁ = 0

initial velocity of the truck, u₂ = 12.5 m/s

let the final velocity of the car, = v₁

let the final velocity of the truck, = v₂

Apply the principle of conservation of linear momentum for elastic collision;

m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂

(715 x 0) + (1490 x 12.5) = 715v₁ + 1490v₂

18625 = 715v₁ + 1490v₂ -----equation (1)

Apply one-directional velocity formula;

u₁ + v₁ = u₂ + v₂

0 + v₁ = 12.5 + v₂

v₁ = 12.5 + v₂

Substitute v₁ into equation (1)

18625 = 715(12.5 + v₂) + 1490v₂

18625 =8937.5 + 715v₂ + 1490v₂

18625 - 8937.5 = 715v₂ + 1490v₂

9687.5 = 2205v₂

v₂ = 9687.5 / 2205

v₂ = 4.393 m/s

solve for v₁

v₁ = 12.5 + v₂

v₁ =  12.5 + 4.393

v₁ = 16.893 m/s

Answer:

Tanong mo po sa guro mo welcome pasensya need ko po ng point

Answer:1 because

Explanation: it’s pointing to the earth and gravity

Pulls things down to earth

Answer:

P = 97.2 W

Explanation:

Given that,

Voltage drop, V = 54 V

The resistance of the resistor, R = 20 Ohms

Current, I = 1.8 A

We need to find the power used by the resistor. The formula used to find the power is given by :

P = VI

Putting all the values,

P = 54 V × 1.8 A

P = 97.2 W

So, the power used by the resistor is 97.2 W.

Answer:

36.87°

Explanation:

Given

Maximum height = 60m

Horizontal distance (range) = 80,m

Required

Initial speed U

Angle of launch

To get the speed, we will use the range formula;

R = U √2H/g

80 = U√2(60)/9.8

80 = U√12.25

80 = 3.5U

U = 80/3.5

U = 22.86m/s

Get the angle of launch

Using the formula

Theta = tan^-1(y/x)

y is the vertical distance

x is the horizontal distance

Theta = tan^-1(60/80)

Theta = tan^-1(0.75)

Theta = 36.87°

Hence the angle of launch is 36.87°

Answer:

[tex]F = \frac{6.67408m_1 m_2}{10^{11}r^2}[/tex]

Explanation:

Given

[tex]Object_1 = m_1[/tex]

[tex]Object_2 = m_2[/tex]

[tex]Distance = r[/tex]

Required

Determine the force of attraction

This is calculated as:

[tex]F = \frac{GMm}{d^2}[/tex]

Where

M = mass of object 1

m = mass of object 2

d = distance

Where G = gravitational constant

[tex]G = 6.67408 * 10^{-11}\ m^3 kg^{-1} s^{-2}[/tex]

Substitute these values in

[tex]F = \frac{GMm}{d^2}[/tex]

[tex]F = \frac{6.67408 * 10^{-11} * m_1 * m_2}{r^2}[/tex]

[tex]F = \frac{6.67408 * m_1 * m_2* 10^{-11}}{r^2}[/tex]

[tex]F = \frac{6.67408m_1 m_2* 10^{-11}}{r^2}[/tex]

[tex]F = \frac{6.67408m_1 m_2}{10^{11}*r^2}[/tex]

[tex]F = \frac{6.67408m_1 m_2}{10^{11}r^2}[/tex]

Answer:

-20°C

Explanation:

The specific heat capacity of ice using the cgs system is 0.5cal/g°C

The enthalpy change is calculated as follows

ΔH=MC∅ where M represents mass C represents specific heat and ∅ represents the temperature change.

10cal = 2g×0.5cal/g°C×∅

∅=10cal/(2g×0.5cal/g°C)

∅=10°C

Final temperature= -30°C+ 10°C= -20°C

Answer:

-20 degrees Celsius

djsksjhdnenhxndjjdjd

Answer:

0.752 m/s

Explanation:

m1 = 3.00kg

u1 = 5.05m/s

m2 = 2.76kg

u2 = -3.66m/s

According to the law of conservation of momentum,

m1u1 + m2u2 = (m1+m2)v

3(5.05) + 2.76(-3.66) = (5.05+2.76)v

15.15 - 9.2736 = 7.81v

5.8764 = 7.81v

v = 5.8764/7.81

v = 0.752m/s

Answer:

High specific heat -> takes more energy to raise/lower object's temperature

Low specific heat -> takes less energy to raise/lower object's temperature

Explanation:

The specific heat capacity is the amount of heat required to raise the temperature of something per unit of mass.

A high specific heat value for an object means it takes more energy to raise or lower that object's temperature. A low specific heat value for an object means it does not take very much energy to heat or cool that object.

Answer:

3.94 s

Explanation:

Take down to be positive.  Given:

Δy = 76.0 m

v₀ = 0 m/s

a = 9.8 m/s²

Find: t

Δy = v₀ t + ½ at²

76.0 m = (0 m/s) t + ½ (9.8 m/s²) t²

t = 3.94 s

Answer:

gₓ = 1.4 g = 13.8 m/s²

Explanation:

The time period of simple pendulum on earth is given as:

T = 2π√(L/g)

where,

L = Length of pendulum

g = acceleration due to gravity on the surface of earth = 9.8 m/s²

T = Time Period on Earth

but, on the other planets, it becomes:

Tₓ = 2π√(L/gₓ)

where,

Tₓ = Time Period on Surface of Other Planet

gₓ = acceleration due to gravity on other planet  = ?

It is given that:

Tₓ = 71% of T

Tₓ = 0.71 T

using values:

2π√(L/gₓ) = (0.71) 2π√(L/g)

√(1/gₓ) = (0.71)√(1/g)

squaring both sides:

1/gₓ = 0.71/g

gₓ = g/0.71

gₓ = 1.4 g = 13.8 m/s²

Answer:

wind energy is safe

Explanation:

because it just is

Answer:

Wind energy isn't perfect, but better than the alternatives. There is a risk of falling off a turbine in maitenence and there are instances where birds fly into the blades, however there are far more casualties as a result of coal and other fossil fuel extraction.

Explanation:

Answer:

is that a question?

Explanation:

thankyou for the points

Answer:

A)828.8Hz

B)869.2Hz

Explanation:

Here is a complete question;

What frequency is received by a person watching an oncoming ambulance moving at 115 km/h and emitting a steady 753 Hz sound from its siren? Speed of sound is 345m/s

b. What frequency does she receive after the ambulance has passed?

Vs= speed of the ambulance

, We convert to m/s for unit consistency

= 115 km/h= 115km× 1000m/1m × 1hr/3600s= 31.94m/s

Dopler effect is when observed frequency of wave changes with respect to the source or when observed moves relative to transmitting medium can be expressed as

f'=[ (v + vo)/(v- vs)]*f

=[ (v )/(v- vs)]*f

The sign vo and vs depends on vthe direction of the velocity

f= frequency of ambulance siren= 753Hz

v= speed of sound in air= 345m/s

Vo= speed of observer= 0

A) we are to determine the f' of ambulance as heard by person as ambulance approaching.

To find the frequency f' observed by the person we use the expresion below

Then substitute the values

f'=[ (v )/(v- vs)]*f

=[ (345)/(345-31.94)]×753

= 828.8Hz

B)What frequency does she receive after the ambulance has passed?

To find the frequency f' observed by the person we use the expresion below

Then substitute the values

f'=[ (v )/(v + vs)]*f

=[ (345)/(345 + 31.94)]×753

= 869.2Hz

=

Answer:

Fluorine is the most reactive

Explanation:

Among the halogens, fluorine, chlorine, bromine, and iodine, fluorine is the most reactive one. It forms compounds with all other elements except the noble gases helium (He), neon (Ne) and argon (Ar), whereas stable compounds with krypton (Kr) and xenon (Xe) are formed.