As electric current moves through a wire, heat generated by resistance is conducted through a layer of insulation and then convected to the surrounding air. The steady-state temperature of the wire can be computed as

Answer:

40m/s

Explanation:

a=g

u=0

s=81

v²=u²+2as

v²=2(9.81)(81)

v=√1587.6=39.8446985181≈40m/s

The velocity of the roller coaster car each time it reaches the bottom is 40 ms⁻¹. The correct option is (A).

The rate at which the position of an object changes with respect to time is described by the physical quantity known as velocity. It has both magnitude and direction because it is a vector quantity.

Given:

Initial velocity, u = 0 m/s

Acceleration, a = -9.8 ms⁻²

Distance, d = 81 m

From the third equation of motion:

v² = u² - 2as

v² = 0 - 2×(-9.8)×81

v = 40 ms⁻¹

Hence, the velocity of the roller coaster car is 40 ms⁻¹. The correct option is (A).

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Answer:

1. The force of the car engine.

Explanation:

We shall see the effect and role played by each force, one by one, as follows:

1. The force of car engine:

The engine produces a force through combustion that is converted to mechanical work through the shaft. This work is then transmitted to the wheels of the car that cause the motion in the car and increase its kinetic energy.

2. Air Resistance:

It is the opposing force of air that tries to reduce the motion of the car and as a result, reduce its kinetic energy.

3. Frictional Force between road and tire:

It is also the opposing force of air that tries to reduce the motion of the car and as a result, reduce its kinetic energy.

4. Gravity:

Gravity pulls everything towards the center of Earth so it does not have much significant role in horizontal motion like this.

Hence, the force of the car engine did the work that increased the car's kinetic energy.

Answer:

argon (Ar)

Explanation:

Argon is the element from the given choices with a complete valence electron shell.

The valence electron shell is the outermost shell of an atom.

Answer:

argon (Ar)

Explanation:

Answer:

  y =  - 0.050 sin (131.59t )

Explanation:

In this exercise we are told to approximate the movement of a piston to the simple harmonic movement

          y = A cos (wt + Ф)

in this case they indicate that the stroke (C) of the piston is twice the amplitude

          C = 2A

          A = C / 2

angular velocity is related to frequency

          w = 2π f

let's substitute

         y = [tex]\frac{C}{2}[/tex] cos (2π f t +Ф)

To find the phase (fi) we will use the initial conditions, the piston starts at the midpoint of the stroke, if we create a reference system where the origin is at this point

         y = 0 for  t = 0

we substitute in the equation

        0 = \frac{C}{2} cos (0 + Ф)

The we sew zero values ​​for the angles of Ф = π/2 rad

we substitute in the initial equation

      y = \frac{C}{2} cos (2π f t + π/2)

let's use the double angle relationship

     cos ( a +90) = cos a cos 90 - sin a sin 90

     cos (a+90) = - sin a

       y = -\frac{C}{2} sin (2πf t )

let's reduce the frequency to SI units

        f = 200 rpm (2π rad / 1rev) (1 min / 60s) = 20.94 rad / s

we substitute the given values

       y = - [tex]\frac{0.100}{2}[/tex]  sin (2π 20.94 t )

       y =  - 0.050 sin (131.59t )

Answer:

The magnitude of the average acceleration of the ball during this time interval is 1.238 x 10⁴ m/s².

Explanation:

Given;

mass of the super ball, m = 50 g = 0.05 kg

initial velocity of the ball, u = 29.5 m/s

final velocity of the ball, v = -20.0 m/s (negative because it rebounds)

time of contact of the ball and the wall, t = 4 ms = 4 x 10⁻³ s

The force exerted on the brick wall by the ball is given as;

[tex]F = ma\\\\ma = \frac{m(v-u)}{t} \\\\a = \frac{v-u}{t} \\\\a = \frac{(-20) - 29.5}{4.0 \ \times \ 10^{-3}} \\\\a = \frac{-49.5}{4.0 \ \times \ 10^{-3}} \\\\a = -1.238 \times 10^4 \ m/s^2\\\\|a| = 1.238 \times 10^4 \ m/s^2[/tex]

Therefore, the magnitude of the average acceleration of the ball during this time interval is 1.238 x 10⁴ m/s².

Non-Malleable and Ductile: Non-metals are very brittle, and cannot be rolled into wires or pounded into sheets. Conduction: They are poor conductors of heat and electricity. Luster: These have no metallic luster and do not reflect light.

Group 15, the nitrogen family, contains two nonmetals: nitrogen and phosphorus. These non-metals usually gain or share three electrons when reacting with atoms of other elements. Group 16, the oxygen family, contains three nonmetals: oxygen, sulfur, and selenium.

Elements: Nitrogen; Oxygen; Phosphorus; Selenium...

Answer:

25.3J

Explanation:

Given parameters:

Mass of aluminum  = 3.05g

Initial temperature  = 10.8 °C

Final temperature  = 20 °C

Specific heat  = 0.9J/g °C

Unknown:

Amount of heat needed for the temperature to change  = ?

Solution:

To solve this problem, we use the expression:

       H  = m C Ф  

H is the amount of heat

m is the mass

C is the specific heat capacity

Ф is the change in temperature

     H  = 3.05 x 0.901 x (20 - 10.8) = 25.3J

Answer:

Force = 2240 Newton.

Explanation:

Given the following data;

Mass A= 65kg

Mass B = 215kg

Acceleration = 8m/s²

To find the force;

Force is given by the multiplication of mass and acceleration.

Mathematically, Force is;

[tex] F = ma[/tex]

Where;

F represents force.

m represents the mass of an object.

a represents acceleration.

First of all, we would have to find the total mass.

Total mass = Mass A + Mass B

Total mass = 65 + 215

Total mass = 280kg

Substituting into the equation, we have

[tex] Force = 280 * 8 [/tex]

Force = 2240 Newton.

Answer:

Zero

Explanation:

Appearing to throw the ball but still holding on to it means the recoil velocity will be zero because the recoil velocity is defined as the backward velocity as a result of throwing an object or shooting a bullet. In this case the object was not thrown and thus there is no recoil velocity.

Answer:

a) Average speed is 24.04 m/s

b) the rms speed is 25.84 m/s

c) the most probable speed is 16 m/s

Explanation:

Given the data in the question;

a) Determine the average speed.

To determine the average speed, we simply divide total some of speed by number of particles;

Average speed =  [(2×11 m/s)+(7×16 m/s)+(4×19 m/s)+(3×26 m/s)+(6×31 m/s)+(1×37 m/s)+(2×45 m/s)] / 25    

= 601 / 25

= 24.04 m/s

Therefore, Average speed is 24.04 m/s

b) Determine the rms speed

we know that  (rms speed)² = sum of square speed / total number of particles

so

(rms speed)² =  [(2×11²)+(7×16²)+(4×19²)+(3×26²)+(6×31²)+(1×37²)+(2×45²)] / 25

(rms speed)² =  16691 / 25

(rms speed)² =  667.64

(rms speed) = √ 667.64

(rms speed) = 25.84 m/s

Therefore, the rms speed is 25.84 m/s

c) Determine the most probable speed.

Most particles (7) have velocity 16 m/s

i.e 7 is the maximum number of particle for a particular speed ,

Therefore, the most probable speed is 16 m/s

Answer:

e.

Explanation:

       [tex]\Delta y = v_{o} * t - \frac{1}{2} *g*t^{2} (2)[/tex]

        [tex]h =\frac{1}{2} *g*t^{2} (3)[/tex]

Answer:

3.28 degree

Explanation:

We are given that

Distance between the ruled lines on a diffraction grating, d=1900nm=[tex]1900\times 10^{-9}m[/tex]

Where [tex]1nm=10^{-9} m[/tex]

[tex]\lambda_2=400nm=400\times10^{-9}m[/tex]

[tex]\lambda_1=700nm=700\times 10^{-9}m[/tex]

We have to find  the angular width of the gap between the first order spectrum and the second order spectrum.

We know that

[tex]\theta=sin^{-1}(\frac{m\lambda}{d})[/tex]

Using the formula

m=1

[tex]\theta_1=sin^{-1}(\frac{1\times700\times 10^{-9}}{1900\times 10^{-9}})[/tex]

[tex]\theta=21.62^{\circ}[/tex]

Now, m=2

[tex]\theta_2=sin^{-1}(\frac{2\times400\times 10^{-9}}{1900\times 10^{-9}})[/tex]

[tex]\theta_2=24.90^{\circ}[/tex]

[tex]\Delta \theta=\theta_2-\theta_1[/tex]

[tex]\Delta \theta=24.90-21.62[/tex]

[tex]\Delta \theta=3.28^{\circ}[/tex]

Hence, the angular width of the gap between the first order spectrum and the second order spectrum=3.28 degree

Answer:

Explanation:

From the question we are told that

Work done [tex]W=2820[/tex]

a)Generally the heat flow for an adiabatic process is 0 (zero)

[tex]Q= U + W =>0[/tex]

[tex]Q=0[/tex]

b)Generally Change in internal energy of gas is mathematically given by

Since [tex]W=-2820J[/tex]

Therefore

[tex]U=2820[/tex]

Giving

[tex]Q= 2820 -2820[/tex]

[tex]Q=O[/tex]

c)With increases in internal energy brings increase in temperature

Therefore

Energy increases

Answer:

D = -4/7 = - 0.57

C = 17/7 = 2.43

Explanation:

We have the following two equations:

[tex]3C + 4D = 5\ --------------- eqn (1)\\2C + 5D = 2\ --------------- eqn (2)[/tex]

First, we isolate C from equation (2):

[tex]2C + 5D = 2\\2C = 2 - 5D\\C = \frac{2 - 5D}{2}\ -------------- eqn(3)[/tex]

using this value of C from equation (3) in equation (1):

[tex]3(\frac{2-5D}{2}) + 4D = 5\\\\\frac{6-15D}{2} + 4D = 5\\\\\frac{6-15D+8D}{2} = 5\\\\6-7D = (5)(2)\\7D = 6-10\\\\D = -\frac{4}{7}[/tex]

D = - 0.57

Put this value in equation (3), we get:

[tex]C = \frac{2-(5)(\frac{-4}{7} )}{2}\\\\C = \frac{\frac{14+20}{7}}{2}\\\\C = \frac{34}{(7)(2)}\\\\C = \frac{17}{7}\\[/tex]

C = 2.43

This question is incomplete, the complete question is;

According to information found in an old hydraulics book, the energy loss per unit weight of fluid flowing through a nozzle connected to a hose can be estimated by the formula; h= (0.04 to 0.09)(D/d)⁴V²/2g

where h is the energy loss per unit weight, D the hose diameter, d the nozzle tip diameter, V the fluid velocity in the hose, and g the acceleration of gravity.

Do you think this equation is valid in any system of units

Answer:

YES, the equation is a general equation that is valid in any system of units

Explanation:

Given the data in the question;

h = (0.04 to 0.09)(D/d)⁴ × [tex]\frac{V^{2} }{2g}[/tex]

so

[ N.m/N ] = (0.04 to 0.09) ( m/m)² × (m²/s²)1/2 × (s²/m)

[ N.L/N ] = (0.04 to 0.09) ( L⁴/L⁴) × (L²/T²)1/2 × (T²/L)

∴ [ L ] = (0.04 to 0.09) [L]

So as each term in the equation must have the same dimensions, the constant term (0.04 to 0.09) must be without dimension.

Therefore, YES, the equation is a general equation that is valid in any system of units

Answer:

Explanation:

Fluid A :

Δ V = Change in volume = (3000 - 2804) x 10⁻⁶ m³ = 196 x 10⁻⁶ m³

volume strain = Δ V / V  = 196 x 10⁻⁶ / 3000 x 10⁻⁶

= .06533

Δ P = increase in pressure = 6 x 10⁷ Pa

E = Δ P / volume strain = 6 x 10⁷ / .06533 = 91.84 x 10⁷ Pa = .92 GPa .

It is Acetone .

Fluid B :

Δ V = Change in volume = (3000 - 2862) x 10⁻⁶ m³ = 138 x 10⁻⁶ m³

volume strain = Δ V / V  = 138 x 10⁻⁶ / 3000 x 10⁻⁶

= .046

Δ P = increase in pressure = 6 x 10⁷ Pa

E = Δ P / volume strain = 6 x 10⁷ / .046 = 130.43  x 10⁷ Pa = 1.3  GPa .

It is Gasoline  .

Fluid C :

Δ V = Change in volume = (3000 - 2916) x 10⁻⁶ m³ = 84 x 10⁻⁶ m³

volume strain = Δ V / V  = 84 x 10⁻⁶ / 3000 x 10⁻⁶

= .028

Δ P = increase in pressure = 6 x 10⁷ Pa

E = Δ P / volume strain = 6 x 10⁷ / .028 = 214.28 x 10⁷ Pa = 2.14  GPa .

It is Water   .

Static friction (magnitude Fs) keeps the car on the road, and is the only force acting on it parallel to the road. By Newton's second law,

Fs = m a = W a / g

(a = centripetal acceleration, m = mass, g = acceleration due to gravity)

We have

a = v ² / R

(v = tangential speed, R = radius of the curve)

so that

Fs = W v ² / (g R)

Solving for v gives

v = √(Fs g R / W)

Perpendicular to the road, the car is in equilibrium, so Newton's second law gives

N - W = 0

(N = normal force, W = weight)

so that

N = W

We're given a coefficient of static friction µ = 0.4, so

Fs = µ N = 0.4 W

Substitute this into the equation for v. The factors of W cancel, so we get

v = √((0.4 W) g R / W) = √(0.4 g R) = √(0.4 (9.80 m/s²) (105 m)) ≈ 20.3 m/s

Answer:

The constant rate of acceleration required in order to accomplish this is 1.921 feet per square second.

Explanation:

Let suppose that car accelerates uniformly in a rectilinear motion. Given that initial and final speeds and travelled distances are known, then the acceleration needed by the vehicle ([tex]a[/tex]), measured in feet per square second, is determined by the following kinematic formula:

[tex]a = \frac{v_{f}^{2}-v_{o}^{2}}{2\cdot \Delta x }[/tex] (1)

Where:

[tex]v_{o}[/tex], [tex]v_{f}[/tex] - Initial and final speeds, measured in feet per second.

[tex]\Delta x[/tex] - Travelled distance, measured in feet.

If we know that [tex]v_{o} = 34.907\,\frac{ft}{s}[/tex], [tex]v_{f} = 67.027\,\frac{ft}{s}[/tex] and [tex]\Delta x = 852\,ft[/tex], then acceleration needed to accomplish the task is:

[tex]a = 1.921\,\frac{ft}{s^{2}}[/tex]

The constant rate of acceleration required in order to accomplish this is 1.921 feet per square second.

Answer: C

Explanation: 60 divided by 4 =15

Velocity can be defined as the rate of change of distance with time

Given data

Acceleration = 4/ms^2

Distance = 60m

Initial Velocity U= 0

Final Velocity V= ?

The expression for velocity is given by

V^2= U^2+2as

Let us substitute our given data into the expression

V^2 = 0^2 + 2*4*60

V^2 = 480

Square both sides

V= √480

V= 21.9 meters/second

V= 22 meters/seconds Approx.

The correct answer is option B

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Answer:

4.79m/s

Explanation:

According to law of conservation of momentum;

The sum of momentum of the bodies before collision is equal to the momentum after collision.

m1u1 + m2u2 = (m1+m2)v

Given;

m1 = 0.3kg

u1 = 2.30m/s

m2 = 0.0225kg

u2 = 38m/s

Required

speed of the arrow after passing through the target v

Substituting the given data into the formula

0.3(2.3) + 0.0225(38) = (0.3 + 0.0225)v

0.69 + 0.855 = 0.3225v

1.545 = 0.3225v

v = 1.545/0.3225

v = 4.79m/s

Hence the speed of the arrow after passing through the target is 4.79m/s

Answer:

x = 1.04866

Explanation:

Force can be defined from power energy by the expressions

          F = [tex]- \frac{ dU}{ dx}[/tex]

in this case we are the expression of the potential energy

          U = [tex]\frac{2.6}{x^{8} } - \frac{4.3}{ x^{4} }[/tex]

let's find the derivative

         dU / dx = 2.6 ( [tex]\frac{-8}{x^{9} }[/tex]) - 4.3 ([tex]\frac{-4}{ x^{5} }[/tex])

         dU / dx = [tex]- \frac{20.8}{ x^{9} } + \frac{17.2 }{ x^{5} }[/tex]

we substitute

          F = + \frac{20.8}{ x^{9} }  - \frac{17.2 }{ x^{5} }

at the equilibrium point the force is zero, so

           [tex]\frac{20.8}{ x^{9} } = \frac{17.2}{ x^{5} }[/tex]

           20.8 / 17.2 = x⁴

            x⁴ = 1.2093

             x = [tex]\sqrt[4]{ 1.2093}[/tex]

             x = 1.04866

Answer:

a. 10.5 s b. 6.6 s

Explanation:

a. The driver's perception/reaction time before drinking.

To find the driver's perception time before drinking, we first find his deceleration from

v² = u² + 2as where u = initial speed of driver = 50 mi/h = 50 × 1609 m/3600 s = 22.35 m/s, v = final speed of driver = 0 m/s (since he stops), a = deceleration of driver and s = distance moved by driver = 385 ft = 385 × 0.3048 m = 117.35 m

So, a = v² - u²/2s

substituting the values of the variables into the equation, we have

a = v² - u²/2s

a = (0 m/s)² - (22.35 m/s)²/2(117.35 m)

a =  - 499.52 m²/s²/234.7 m

a = -2.13 m/s²

Using a = (v - u)/t where u = initial speed of driver = 50 mi/h = 50 × 1609 m/3600 s = 22.35 m/s, v = final speed of driver = 0 m/s (since he stops), a = deceleration of driver = -2.13 m/s² and t = reaction time

So, t = (v - u)/a

Substituting the values of the variables into the equation, we have

t = (0 m/s - 22.35 m/s)/-2.13 m/s²

t = - 22.35 m/s/-2.13 m/s²

t = 10.5 s

b. The driver's perception/reaction time after drinking.

To find the driver's perception time after drinking, we first find his deceleration from

v² = u² + 2as where u = initial speed of driver = 50 mi/h = 50 × 1609 m/3600 s = 22.35 m/s, v = final speed of driver = 30 mi/h = 30 × 1609 m/3600 s = 13.41 m/s, a = deceleration of driver and s = distance moved by driver = 385 ft = 385 × 0.3048 m = 117.35 m

So, a = v² - u²/2s

substituting the values of the variables into the equation, we have

a = v² - u²/2s

a = (13.41 m/s)² - (22.35 m/s)²/2(117.35 m)

a = 179.83 m²/s² - 499.52 m²/s²/234.7 m

a = -319.69 m²/s² ÷ 234.7 m

a = -1.36 m/s²

Using a = (v - u)/t where u = initial speed of driver = 50 mi/h = 50 × 1609 m/3600 s = 22.35 m/s, v = final speed of driver = 30 mi/h = 30 × 1609 m/3600 s = 13.41 m/s, a = deceleration of driver = -1.36 m/s² and t = reaction time

So, t = (v - u)/a

Substituting the values of the variables into the equation, we have

t = (13.41 m/s - 22.35 m/s)/-1.36 m/s²

t = - 8.94 m/s/-1.36 m/s²

t = 6.6 s

Answer: you divide total distance by time. To get the time, divide total distance by speed. To get distance,  multiply speed times the amount of time.

Explanation:

I hope this helps

Answer: he can only make it over 5 buses

Explanation:

Given the data in the question;

we know that range is expressed as;

R = (V₀²sin2∅₀)/g

V₀ is the initial velocity( 25.4 m/s), ∅₀ is the angle of projection( 64.8°), g is acceleration due to gravity( 9.8 m/s²),

so we substitute

R = ((25.4)²sin2(64.8))/9.8

R = 50.7 m

now, them number of buses will be;

n = R / bus length

given that bus length is 10.0 m

we substitute

n = 50.7 m / 10.0

n = 5.07 ≈ 5

Therefore, he can only make it over 5 buses

Answer:

a) vx = -12.7 m/s vy = -56.7m/s

b) v= 58.1 m/s

c) θ = 77.4º S of W

Explanation:

a)

       [tex]v_{ps} = -44m/s (1)[/tex]

       [tex]v_{we} = - 18m/s * cos (45) = -12.7 m (2)[/tex]

       [tex]v_{ws} = - 18m/s * cos (45) = -12.7 m (3)[/tex]

        [tex]v_{e} = v_{x} = -12.7 m/s (4)[/tex]

b)

        [tex]v = \sqrt{(-12.7m/s)^{2} + (-56.7m/s)^{2}} = 58.1 m/s (6)[/tex]

c)

       [tex]tg_{\theta} =\frac{v_{y} }{v_{x} } = \frac{(-56.7m/s)}{(-12.7m/s} = 4.46 (7)[/tex]

        tg⁻¹ θ = tg⁻¹ (4.46) = 77.4º S of W. (8)

Answer:

Explanation:

Magnetic field due to current at a distance of 4.4 cm

B = 10⁻⁷ x 2 x 5.2 / 4.4 x 10⁻²           [ B = 10⁻⁷ x 2i / r = ]

= 2.36 x 10⁻⁵ T.

Force on moving electron = Bqv , B is magnetic field , q is charge and v is velocity of charge .

Force = 2.36 x 10⁻⁵  x 1.6 x 10⁻¹⁹ x 6.2 x 10⁴

= 23.41 x 10⁻²⁰ N .

This force will be perpendicular to the direction of current .

Answer:

5766.7 K

Explanation:

We are given that

Radius of Sun , R=[tex]6.96\times 10^{8} m[/tex]

Distance between the Sun and the Earth, D=[tex]1.50\times 10^{11}m[/tex]

Irradiance arriving on the Earth is the value for AMO=[tex]1350W/m^2[/tex]

We have to find the temperature at the surface of the Sun.

We know that

Temperature ,T=[tex](\frac{K_{sc}D^2}{\sigma R^2})^{\frac{1}{4}}[/tex]

Where [tex]K_{sc}=1350 W/m^2[/tex]

[tex]\sigma=5.67\times 10^{-8}watt/m^2k^4[/tex]

Using the formula

[tex]T=(\frac{1350\times (1.5\times 10^{11})^2}{5.67\times 10^{-8}\times (6.96\times 10^{8})^2})^{\frac{1}{4}}[/tex]

T=5766.7 K

Hence, the temperature at the surface of the sun=5766.7 K

Answer:

the way a mineral breaks apart

Explanation:

The way a mineral breaks apart involves fracture and cleavage.

These characteristics are very important in mineral identification especially during physical observations. Minerals have different cleavage properties and fracture planes.

Answer:

A:the way a mineral breaks apart

Explanation:

Answer:

a. Photogates placed at the beginning, end, and at various locations along the track that the car travels on.

b. A meterstick to measure the distance of the track that the car travels on.

Explanation:

Physics can be defined as the field or branch of science that typically deals with nature and properties of matter, motion and energy with respect to space, force and time.

In this scenario, a student is provided with a battery-powered toy car that the manufacturer claims will always operate at a constant speed. The student must design an experiment in order to test the validity of the claim.

Therefore, to test the validity of the claim, the student should use the following measuring tools;

a. Photogates placed at the beginning, end, and at various locations along the track that the car travels on. This device is typically used to measure time with respect to the rate of change of the interruption or block of an infra-red beam.

b. A meterstick to measure the distance of the track that the car travels on.

Hence, with these two devices the student can effectively measure or determine the validity of the claim.