A car of mass 500 kg is moving at a speed of 1.2 m/s. A man pushes the car,
increasing the speed to 2 m/s. How much work did the man do?
A. 640 J
B. 360 J
C. 1360 J
D. 1000 J

Answer:

belpw

Explanation:

The distance prior to the sliding friction dispersing her energy would be:

- The distance will remain unaffected by the sliding friction i.e. 354m

As we know, When Sliding friction dissolves her energy, leading her Kinetic Energy to turn 0 on coming to the state of rest. So,

[tex]1/2 mv^2 - 1/2 mu^2 = -W[/tex]            (∵ Work in -ve denotes it is done opposite to friction)

Given that,

m(mass) [tex]= 50 kg[/tex]

v(velocity) [tex]= 30 km/hr[/tex] or [tex]8.33 m/s[/tex]

The coefficient of Kinetic Friction [tex]= 0.01[/tex]

g(gravitational force) [tex]= 9.8 m/s^2[/tex]

Initial Velocity(u) [tex]= 30[/tex] × [tex]1000/3600 m/s[/tex]

[tex]= 8.33 m/s[/tex]

Now by employing the provided values,

[tex]F =[/tex] μ[tex]mg[/tex]

[tex]= (0.01) (50) (9.8)[/tex]

[tex]= 4.9[/tex]

∵ [tex]F = 4.9 N[/tex]

By using the above expression, we will find the distance;

[tex]1/2 mv^2 - 1/2 mu^2 = -W[/tex]

⇒ [tex]1/2 (50) (0)^2 - 1/2 (50) (8.33)^2 = -4.9(S)[/tex]

⇒ [tex]1734.7225 = 4.9S[/tex]

⇒ [tex]S = 1734.7225/4.9[/tex]

∵ [tex]S = 354 m[/tex]

Because [tex]1/2 mv^2 - 1/2 mu^2 = -W[/tex]  [tex]= -[/tex] μmgS

⇒ [tex]S = (u^2 - v^2)[/tex]/2μ[tex]g[/tex]

Thus, the distance will remain unaffected by the sliding friction i.e. 354m

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Answer:

157n is the correct answer

Answer:

7.51

Explanation:

The mass of the bat is given to us as:

m = 0.277  kg

,

and its initial velocity is:

v

i  = 4.25  m/s

When the velocity is doubled, the new value becomes:

v f = 4.25 m/s × 2 = 8.5   m/s

.

The formula for kinetic energy is:

K

=

1

2

m

v

2

.

The change in kinetic energy is:

Δ K = 1 /2( m ) ( v2 f − v 2 i ) = 1 2 ( 0.277)

10-2.5=7.5J

7.51  J

.

The bat gained 7.51 joules.

Answer:

D_y = 414.38m

Explanation:

D_y = D*sin(x)

D_y = 673m*sin(38°)

D_y = 414.38m

Answer:

B) (80m/s/s)(70kg)=5600N + Fg = 5600N+(70kg)(9.8N/kg)~5600N+700N=6300N

Explanation:

The total force by the chair is given by the following formula:

[tex]F = m(g+a)[/tex]

where,

F = Force = ?

m = mass of person = 70 kg

g = value of acceleration dueto gravity = 9.81 m/s²

a = acceleration of ejection seat = 8g = 80 m/s²

Therefore,

[tex]F = mg+ma \\F = (70\ kg)(9.8\ m/s^2)+(70\ kg)(80\ m/s^2)\\F = 6300 N[/tex]

Therefore, the correct option is:

B) (80m/s/s)(70kg)=5600N + Fg = 5600N+(70kg (9.8N/kg)~5600N+700N=6300N

Answer:

Changes in climate conditions, especially the warming of global temperatures increases the likelihood of weather-related natural disasters. ... This is most visible when seen through changes in the intensity and frequency of droughts, storms, floods, extreme temperatures and wildfires.

Answer:B

Explanation: The answer explains it

The molecules that make up olive oil are longer than those that make up alcohol, so they have more resistance to sliding past one another. The correct answer is option A.

This higher resistance to flow leads to a higher viscosity in olive oil compared to rubbing alcohol. Viscosity is a measure of a fluid's resistance to flow, and longer molecules in olive oil result in stronger intermolecular forces and entanglements. In contrast, rubbing alcohol has shorter and less complex molecules, which allow them to move more freely and exhibit lower viscosity. The molecular structure and intermolecular forces play a crucial role in determining the viscosity of liquids, making olive oil more viscous than rubbing alcohol. Option A is correct.

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Answer:

Newton's third law states that for every action, there is an equal and opposite reaction. That means when you exert a force on an object, the object exerts a force back on you. ... Using shock-absorbing materials can help reduce the amount of force exchanged between the ground and the egg.

Explanation:

I hope it helps you

When one of the tall straws hits the ground, the energy is transferred to the center of the pyramid and then to the egg, but as the middle straw is connected to the outer surface of the egg, energy enters trying to make the egg rotate. This is governed by Newton's third law.

If an object exerts a force on another object, then another object must exert a force of equal magnitude and opposite direction back on first object.

Examples of Newton's third law are:

A swimmer moves forward by pushing off the side of pool. This way, the wall pushes in opposite direction and giving acceleration.

Another example is rockets move forward by expelling gas backward at high velocity. This means the rocket exerts a large backward force on the gas in the rocket combustion chamber, and the gas therefore exerts a large reaction force forward on the rocket. This reaction force is called thrust.

Helicopters similarly create lift by pushing air down, thereby experiencing an upward reaction force. Birds and airplanes also fly by exerting force on air in a direction opposite to that of whatever force they need. For example, the wings of a bird force air downward and backward in order to get lift and forward motion.

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Solution :

Given expression :

[tex]$\mu_k$[/tex]mgcosθ = mgsinθ − ma

Here, g = 9.8 [tex]m/s^2[/tex] , a = 3.60 [tex]m/s^2[/tex] , θ = 27°

Therefore,

[tex]$\mu_k mg \cos \theta = mg \sin \theta - ma$[/tex]

[tex]$\mu_k mg \cos \theta = m(g \sin \theta - a)$[/tex]

[tex]$\mu_k g \cos \theta = (g \sin \theta - a)$[/tex]

[tex]$\mu_k =\frac{(g \sin \theta-a)}{g \cos \theta}$[/tex]

Mow calculating the coefficient of kinetic friction as follows :

[tex]$\mu_k=\frac{g \sin \theta-a}{g \cos \theta}$[/tex]

[tex]$\mu_k=\frac{9.8 \times \sin 27^\circ-3.60}{9.8 \times \cos 27^\circ}$[/tex]

[tex]$\mu_k=0.097$[/tex]

Answer:

Length = 3.136 meters

Explanation:

Given the following data;

Speed = 345 m/s

Frequency = 440 Hz

To find how long is the tube;

First of all, we would determine the wavelength;

Wavelength = speed/frequency

Wavelength = 345/440

Wavelength = 0.784 m

Next, we would determine how long is the tube using the formula;

[tex] Length = \frac {2n - 1}{4} * wavelength [/tex]

Substituting into the formula, we have;

[tex] Length = \frac {2*1 - 1}{4} * 0.784 [/tex]

[tex] Length = \frac {2 - 1}{4} * 0.784 [/tex]

[tex] Length = \frac {1}{4} * 0.784 [/tex]

Length = 3.136 meters

Answer:

the horizontal component of the force is 50 N

Explanation:

Given;

force applied by the man, F = 100 N

angle of inclination of the force, θ = 60⁰

mass of the dog, m = 20 kg

The horizontal component of the force is calculated as;

[tex]F_x = F\times cos(\theta)\\\\F_x = 100 \ N \times cos(60^0)\\\\F_x = 100\ N \times 0.5\\\\F_x = 50 \ N[/tex]

Therefore, the horizontal component of the force is 50 N

Answer:

The ceramic tile will stand the force of 5 N.

Explanation:

Step 1: Calculate the area (A) of the ceramic tile

We will use the formula for the area of a square.

A = 50 cm × 50 cm = 2500 cm²

Step 2: Convert "A" to in²

We will use the conversion factor 1 in² = 6.45 cm².

2500 cm² × 1 in²/6.45 cm² = 3.9 × 10² in²

Step 3: Calculate the pressure (P) exerted by a force (F) of 5 N

We will use the following expression.

P = F/A

P = 5 N / 3.9 × 10² in² = 0.013 N/in²

Since the pressure exerted would be less than the maximum pressure resisted (40 N/in²), the ceramic tile will stand the force of 5 N.

Answer:

22.36 rad

Explanation:

Applying,

ω = θ/t.............. Equation 1

Where ω  = angular velocity, θ = angular displacement of the baseball, t = time

make θ the subject of the equation

θ = ωt............... Equation 2

From the question,

Given: ω = 350 rev/min = 350(0.10472) = 36.652 rad/s, t = 0.61 s

Substitute these values into equation 1

θ = 0.61(36.652)

θ = 22.36 rad

Hence the angular displacement of the baseball is  22.36 rad

Answer:

A simple pendulum consists of a ball (point-mass) m hanging from a (massless) string of length L and fixed at a pivot point P. When displaced to an initial angle and released, the pendulum will swing back and forth with periodic motion.

Answer: I'd go with Option B if you're allowed to pick One Option Only.

Option A is wrong. Electric Forces arent Non - Conservative. They're Conservative forces.

Option B: We Can Only Define Potential Energies for conservative Forces/fields✅

Option C is wrong. Since the Electric Force is Conservative... It doesn't depend on the path taken.

Option D... There's a Point where the electric Potential Energy is Zero but the separation Distance Would be large.

E is wrong because the Workdone around a closed path is Zero.

The electric potential energy results from the conservative Coulomb forces.

The electric potential energy is the potential energy that results due to the conservative Coulomb forces and is always associated with the set of two charged particles.

Any object can have electric potential energy by two key elements first is its own charge and the second is its position with respect to the other charged particle.

The electric potential energy-containing only one point charge will be zero. Because there are no other sources of electrostatic force against which an external agent must do work in moving the point charge from infinity to its final position.

Thus the electric potential energy results from the conservative Coulomb forces.

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Answer:

[tex]51.34^{\circ}[/tex]

Explanation:

Given that,

x component of a vector = -12 m

The y component of a vector = -15 m

We need to find the direction of a vector. The direction of a vector is given by :

[tex]\tan\theta=\dfrac{y}{x}[/tex]

Put all the values,

[tex]\tan\theta=\dfrac{-15}{-12}\\\\\theta=\tan^{-1}(\dfrac{-15}{-12})\\\\\theta=51.34^{\circ}[/tex]

So, the direction of vector is [tex]51.34^{\circ}[/tex] to x component.

Answer:

NO, 1. is stocks

2. is also stocks

bouquit GARNI IS NUMBER 3

NUMBER 4 IS ACID PRODUCTS

number 5 is brown stock

Explanation:

stocks are bones

Answer:

The net field will be the sum of the fields created by each charge.

where the charge Q in a position r' is given by:

E(r) = k*Q/(r - r')^2

Where k is a constant, and r is the point where we are calculating the electric field.

Then for the charge 3q, in the position r₁ = (-d, 0, 0) the electric field will be:

E₁(r) = k*3q/(r - r₁)^2

While for the other charge of -2q in the position r₂ = (d, 0, 0)

The electric field is:

E₂(r) = -k*2*q/(r - r₂)^2

Then the net field at the point r is:

E(r) = E₁(r) + E₂(r) = k*3q/(r - r₁)^2 + -k*2*q/(r - r₂)^2

E(r) = k*q*( 3/(r - r₁)^2 - 2/(r - r₂)^2)

Then if the we want to find the points r = (x, y, z) such that:

E(r) = 0 = k*q*( 3/(r - r₁)^2 - -k*2*q/(r - r₂)^2)

Then we must have:

0 = ( 3/(r - r₁)^2 - 2/(r - r₂)^2)

Also remember that the distance between two points:

(x, y, z) and (x', y', z') is given by:

D = √( (x - x')^2 + (y - y)^2 + (z -z')^2)

Then we can rewrite:

r - r₁ = √( (x - (-d))^2 + (y - 0 )^2 + (z -0)^2)

       = √( (x + d))^2 + y^2 + z^2)

and

r - r₂ =  √( (x - d)^2 + (y - 0 )^2 + (z -0)^2)

       = √( (x - d))^2 + y^2 + z^2)

Replacing that in our equation we get:

0 = ( 3/(√( (x + d))^2 + y^2 + z^2))^2 - -k*2*q/(√( (x - d))^2 + y^2 + z^2))^2)

0 = (3/((x + d))^2 + y^2 + z^2) - 2/ (x - d))^2 + y^2 + z^2)

We want to find the values of x, y, z such that the above equation is true.

2/ (x - d))^2 + y^2 + z^2) = (3/((x + d))^2 + y^2 + z^2)

2*[((x + d))^2 + y^2 + z^2] = 3*[(x - d))^2 + y^2 + z^2]

2*(x + d)^2  + 2*y^2 + 2*z^2 = 3*(x - d)^2 + 3*y^2 + 3*z^2

2*(x + d)^2 - 3*(x - d)^2 =  3*y^2 + 3*z^2 -  2*y^2 - 2*z^2

2*(x + d)^2 - 3*(x - d)^2  = y^2 + z^2

2*x^2 + 2*2*x*d + 2*d^2 -  3*x^2 + 3*2*x*d - 3*d^2 = y^2 + z^2

-x^2 + 10*x*d - d^2 = y^2 + z^2

we can rewrite this as:

- ( x^2 - 10*x*d + d^2) =  y^2 + z^2

now we can add and subtract 24*d^2 inside the parenthesis to get

- ( x^2 - 10*x*d + d^2 + 24*d^2 - 24*d^2) =  y^2 + z^2

-( x^2 - 2*x*(5d) + 25d^2 - 24d^2) = y^2 + z^2

-(x^2 - 2*x*(5d) + (5*d)^2) + 24d^2 = y^2 + z^2

The thing inside the parenthesis is a perfect square:

-(x - 5d)^2 + 24d^2 = y^2 + z^2

we can rewrite this as:

24d^2 = y^2 + z^2 + (x - 5d)^2

This equation gives us the points (x, y, z) such that the electric field is zero.

Where we need to replace two of these values to find the other, for example, if y = z = 0

24d^2 = (x - 5d)^2

√(24d^2)  = x - 5d

√24*d = x - 5d

√24*d + 5d = x

so in the point (√24*d + 5d, 0, 0) the net field is zero.

Answer:

C. 2666W

Explanation:

m =200kg

h =20m

t =15s

g =10ms^-2

p = mgt/t

=200×20×10/15

=40,000/15

=2666.6

≈2666W

Answer:

the mass of the car is 890 kg

Explanation:

Given;

mass of the man, m = 92 kg

displacement of the car's spring, x = 4.5 cm = 0.045 m

acceleration due to gravity, g = 9.8 m/s²

The spring constant of the car,

f = kx

where;

f is the weight of the man on the car = mg

mg = kx

k = mg/x

k = (92 x 9.8) / 0.045

k = 20,035.56 N/m

The angular speed of car, ω, when the is inside is given as 4.52 rad/s

The total mass of the car and the man is calculated as;

[tex]\omega = \sqrt{\frac{k}{m} } \\\\\omega^2 = \frac{k}{m} \\\\m = \frac{k}{\omega^2} = \frac{20,035.56}{(4.52)^2} = 980.7 \ kg[/tex]

The mass of the car alone = 980.7 kg - 92 kg

                                            = 888.7 kg

                                             ≅ 890 kg

Therefore, the mass of the car is 890 kg

Answer:

Δx Displacement

t Time interval

v0  Initial velocity

v  Final velocity

a  Constant acceleration

Explanation:

I dont know if this helps because these are kinda like, examples... hope it helps tho :)

Answer: [tex]68.75\ kg, 0.06[/tex]

Explanation:

Mary applies a force of 73 N to create an acceleration of [tex]0.48\ m/s^2[/tex]

When She increases force to 84 N, it creates an acceleration of [tex]0.64\ m/s^2[/tex]

Friction opposes the motion of box

[tex]\Rightarrow 73-f=m\times 0.48\quad \ldots(i)\\\Rightarrow 84-f=m\times 0.64\quad \ldots(ii)[/tex]

Subtract (i) from (ii)

[tex]\Rightarrow 11=m(0.64-0.48)\\\Rightarrow m=68.75\ kg[/tex]

Therefore friction is

[tex]\Rightarrow f=73-68.75\times 0.48\\\Rightarrow f=73-33\\\Rightarrow f=40\ N[/tex]

Here, friction is kinetic friction which is given by

[tex]\Rightarrow f=\mu_kmg\\\Rightarrow 40=\mu_k 68.75\times 9.8\\\Rightarrow \mu_k=0.061[/tex]

Answer:

Force is the strength or weight of things that depends on movement. The types of forces are conteact force, spring force, applied force, air resistance force, normal force, frictional force, tension force, and non-contact force.

The voltage across the element is = 240 V

I hope you understand....

Mark me as brainliest....

Thanks...

Answer:

  r = 2,026 10⁹ m  and   T = 2.027 10⁴ s

Explanation:

For this exercise let's use Newton's second law

        F = m a

where the force is electric

        F = [tex]k \frac{q_1q_2}{r^2}[/tex]

Acceleration is centripetal

        a = v² / r

we substitute

        [tex]k \frac{q_1q_2}{r^2} = m \frac{v^2}{r}[/tex]

        r = [tex]k \frac{q_1q_2}{m \ v^2}[/tex]          (1)

let's look for the charge in the insulating sphere

          ρ = q₂ / V

          q₂ = ρ V

the volume of the sphere is

         v = 4/3 π r³

we substitute

        q₂ = ρ [tex]\frac{4}{3}[/tex] π r³

        q₂ = 3 10⁻⁹ [tex]\frac{4}{3}[/tex] π 4³

        q₂ = 8.04 10⁻⁷ C

let's calculate the radius with equation 1

        r = 9 10⁹  1.6 10⁻¹⁹  8.04 10⁻⁷ /(9.1  10⁻³¹ 628 10³)

        r = 2,026 10⁹ m

this is the radius of the electron orbit around the charged sphere.

Since the orbit is circulating, the speed (speed modulus) is constant, we can use the uniform motion ratio

        v = x / t

the distance traveled in a circle is

        x = 2π r

In this case, time is the period

        v = 2π r /T

        T = 2π r /v

let's calculate

        T = 2π 2,026 10⁹/628 103

        T = 2.027 10⁴ s

Answer:

a. El peso = 686 Newton

b. El peso = 113.4 Newton

Explanation:

Dados los siguientes datos;

Masa = 70 kg

Aceleración debida a la gravedad en la luna = 1,62 m/s² una.

a. Para encontrar la fuerza-peso en la Tierra;

Sabemos que la aceleración debida a la gravedad es igual a 9,8 m/s² en el planeta Tierra.

El peso se puede definir como la fuerza que actúa sobre un cuerpo o un objeto como resultado de la gravedad.

Matemáticamente, el peso de un objeto viene dado por la fórmula;

[tex] Peso = mg [/tex]

Dónde;

m es la masa del objeto.

g es la aceleración debida a la gravedad.

Substituting into the formula, we have;

El peso = 70 * 9.8

El peso = 686 Newton

b. To find weight on moon;

Weight = mass * acceleration due to gravity on moon

Weight = 70 * 1.62

Weight = 113.4 Newton

Answer:

a liquid warms gas cools

b solid piece warms and liquid cools

Answer:

the electric field is  3.91 x 10⁶ N/C

Explanation:

Given the data in the question;

Electric field at a point due to point charge is;

E = kq/r²

where k is the constant, r is the distance from centre of terminal to point where electric field is, q is the excess charge placed on the centre of terminal of Van de Graff,a generator

Now, given that r = 3.9 m, k = 9.0 x 10⁹ Nm²/C², q = 6.60 mC = 6.60 x 10⁻³ C

so we substitute into the formula

E = [(9.0 x 10⁹ Nm²/C²)( 6.60 x 10⁻³ C)] / ( 3.9 )²

E = 59400000 / 15.21

E = 3.91 x 10⁶ N/C

Therefore, the electric field is  3.91 x 10⁶ N/C