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Answer:

[tex]W_m=183.495N[/tex]

Explanation:

From the question we are told that:

Weight [tex]W=248Ibs[/tex]

Mass of Weight  [tex]m= 248*0.453[/tex]

                          [tex]m=112.344kg[/tex]

Generally the acceleration due to gravity on the Moon is one-sixth that on Earth.

Therefore

The equation for Weight on Moon is given as

 [tex]W_m=m*g/6[/tex]

 [tex]W_m=122.344*\frac{9.8}{6}[/tex]

 [tex]W_m=183.495N[/tex]

Answer:

F ’= 40.9 lb

Explanation:

The weight of a body is the attraction of the Earth on the body

          F = [tex]G \frac{m M_e}{R_e^2}[/tex]

          F = mg

          m = F / g

          m = 248/32

         m = 7.75 slug

The weight of the body on the moon is the attraction of the body for the satellite

         F ’= [tex]G \frac{mM}{R^2}[/tex]

from the tables the mass and radius of the moon are M = 7.34 10²² kg and R = 1.74 10⁶ m

let's reduce the mass to the SI system

         m = 7.75 slug (14.59 kg / 1 slug) = 113 kg

         F ’= 6.67 10⁻¹¹ 113 7.34 10²² / (1.74 10⁶) ²

         F ’= 1.82 10² N

         F ’= 1.82 10² N (0.2248 lb / 1 N)

         F ’= 40.9 lb

Answer: 6117.58 J

Explanation:

We know that W=Fd*cos(theta) where theta is the angle between the displacement and the force.

In this case, we are given that F=225 N, d=30 m, and theta=25 degrees.

Plugging all this in we get

W=225*30*cos(25)=6117.58 J

Work done by the rope when sailor pulls the boat in the dock is 6930.9 J

The work is defined by the product of force and displacement. Its standard formula is,

[tex]W = F.d.Cos\alpha[/tex]

Here F is force, d is displacement and α is angle subtended by force from horizontal.

      F = 255N, d = 30m, α = 30°

      W = 255×30×Cos30°  

           =7650×0.906

           = 6930.9 J

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Answer:

KE= 1/2mv^2= 1/2*0.0042kg*993m/s= 2.0853joule

Answer:

fjowe

Explanation:

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Answer:

The speed of combined package after the collision is [tex]\frac{\sqrt(2gh)}{4}\\[/tex].

Explanation:

mass of first package = m

height , h = 3 m

mass of second package = 3 m

let the speed of first package is u as it strikes with the second package.

Use the third equation of motion

[tex]v^2 = u^2 + 2 gh \\\\u^2 = 0 + 2 g h \\\\u = \sqrt {2gh}[/tex]

Let the velocity of combined package after the collision is v.

Use the conservation of momentum

[tex]m\times u + 3m \times 0= (m + 3m)\times v\\\\m u = 4mv \\\\v=\frac {u}{4}\\\\v = \frac{\sqrt(2gh)}{4}\\\\[/tex]

Answer:

correct answer is b

Explanation:

The frequency of a wave depends on the properties of medium density and the elasticity properties change the amplitude depends on the energy carried by the wave, that is, the amplitude is proportional to the height of the wave (oscillation).

Consequently the amplitude of independent of the frequency because it depends on different factors.

Therefore when changing the amplitude the wavelength remains constant

the correct answer is b

Answer:

[tex]\boxed {\boxed {\sf a \approx 0.4 \ m/s^2}}[/tex]

Explanation:

According to Newton's Second Law of Motion, force is the product of mass and acceleration.

[tex]F= m \times a[/tex]

The net force is 5 Newtons and the mass is 13 kilograms. Let's convert the units for force to make the problem and unit cancellation easier.

Now we know the values for 2 variables:

Substitute the values into the formula.

[tex]5 \ kg *m/s^2 = 13 \ kg * a[/tex]

Since we are solving for the accleration we must isolate the variable, a. It is being multiplied by 13 kilograms and the inverse of multiplication is division. Divide both sides by 13 kg

[tex]\frac {5 \ kg *m/s^2}{13 \ kg}= \frac{ 13 \ kg *a}{13 \ kg}[/tex]

[tex]\frac {5 \ kg *m/s^2}{13 \ kg}=a[/tex]

The units of kilograms (kg) cancel.

[tex]\frac {5 m/s^2}{13 }=a[/tex]

[tex]0.384615385\ m/s^2=a[/tex]

The original measurements of force and mass ( 5 and 13) have 1 and 2 significant figures. We must round our answer to the least number of sig figs: 1.

For the number we found, that is the tenths place. The 8 in the hundredth place (0.384615385) tells us to round the 3 up to a 4.

[tex]0.4 \ m/s^2 \approx a[/tex]

The acceleration is approximately 0.4 meters per square second.

Answer:

c

Explanation:

Answer:C

Explanation:

Answer:

The minimum thickness of soap film is [tex]2.086\times 10^{-7} m[/tex].

Explanation:

wavelength = 555 nm

refractive index, n = 1.33

For the destructive interference,

the thickness is given by

[tex]t =\frac{m \lambda }{2 n}[/tex]

Here, m is the order, n is the refractive index and [tex]\lambda[/tex] is the wavelength.

For minimum thickness, m = 1

So the thickness is  

[tex]t =\frac{1 \times 555\times 10^{-9} }{2 \times 1.33}\\\\t = 2.086\times 10^{-7} m[/tex]

DL: Activity 2.3 Resistance

Complete the questions based on the Resistance presentation.

a. All resistors ___________ or _____________ the flow of electrons.

b. As resistance __________________ current _______________________

a) limits or opposes

b) increases, decreases

Resistors are electrical devices used to resist, limit, oppose or hinder the flow of electrons in a circuit. This resistance causes a reduction in current and an increase in voltage in the circuit. In order words, as resistance increases, the current decreases and voltage increases.

This was further stated by Ohm's law that states that as long as the resistance in a wire/conductor remains constant, the voltage across it is directly proportional to the current flowing through a conductor. i.e

V = IR

Where;

R = constant called resistance

I = current flowing through the wire

V = voltage across the wire

You can't tell. It depends on other things besides just their distance.

IF the stars are really really "identical", then the magnitude of Star-B is the number that is 6 more than the magnitude of Star-A.

Answer:

The correct answer is - 6.49 × 10^3 mm.

Explanation:

The correct scientific notation of the given subtraction problem is:

6.94 × 10^3 mm - 4.5 × 10^2 mm = _____.

The correct number of significant digits is

a. 6.94 × 10^3 mm = 3

b. 4.5 × 10^2 mm = 2

So subtracting the 6.94 × 10^3 mm - 4.5 × 10^2 mm

= 6940 - 450

= 6.49× 10^3 mm.

Answer:

6.5x 10^3 mm

Explanation:

Answer:

3.416 m/s

Explanation:

Given that:

mass of cannonball [tex]m_A[/tex] = 72.0 kg

mass of performer [tex]m_B[/tex] = 65.0 kg

The horizontal component of the ball initially [tex]\mu_{xA}[/tex] = 6.50 m/s

the final velocity of the combined system v = ????

By applying the linear momentum of conservation:

[tex]m_A \mu_{xA}+m_B \mu_{xB} = (m_A+m_B) v[/tex]

[tex]72.0 \ kg \times 6.50 \ m/s+65.0 \ kg \times 0 = (72.0 \ kg+65.0 \ kg) v[/tex]

[tex]468 kg m/s + 0 = (137 kg)v[/tex]

[tex]v = \dfrac{468\ kg m/s }{137 \ kg}[/tex]

v = 3.416 m/s

Answer:

20J

Explanation:

[tex]KE = \frac{1}{2} mv^{2} = \frac{1}{2} (10)(2)^{2} =20J[/tex]

Answer:

the final speed of the 0.75 kg cart is 2.86 m/s

Explanation:

Given;

mass of the air glider, m₁ = 1.0 kg

initial speed of the air glider, u₁ = 2.5 m/s

mass of the stationary cart, m₂ = 0.75 kg

initial speed of the stationary cart, u₂ = 0

Let the final speed of the stationary cart = v₂

Also, let the final speed of the air glider = v₁

Since the air glider has a spring bumper, the collision will be elastic.

Apply the following principle of conservation of linear momentum for elastic collision.

m₁u₁  +  m₂u₂  = m₁v₁   +   m₂v₂

(1 x 2.5)  + 0.75(0)  =  v₁   +  0.75v₂

2.5 = v₁  +  0.75v₂

v₁ = 2.5 - 0.75v₂ ----------- (1)

Apply one-dimensional velocity concept since the collision occured in one direction;

u₁ + v₁  = u₂  +  v₂

2.5  +  v₁   = 0   +  v₂

v₁ = v₂  - 2.5 ----- (2)

solve (1) and (2) together;

v₂  - 2.5 = 2.5 - 0.75v₂

v₂ + 0.75v₂ = 2.5  +  2.5

1.75v₂ = 5

v₂ = 5 / 1.75

v₂ = 2.86 m/s

Therefore, the final speed of the 0.75 kg cart is 2.86 m/s

Answer:

C: Mass of body

Explanation:

Upthrust is defined as the upward force that a liquid will exert on a body floating atop it.

Now, Formula for upthrust is;

Upthrust = density of liquid × volume of the body × acceleration due to gravity.

From the formula, we can see that upthrust depends on density, volume and acceleration due to gravity.

Thus, looking at the options, the one that doesn't apply is mass of body.

Answer:

a yard

Explanation:

Answer:

P = 0.25 W

Explanation:

Given that,

The emf of the battry, E = 2 V

The resistance of a bulb, R = 16 ohms

We need to find the power delivered to the bulb. We know that, the formula for the power delivered is given by :

[tex]P=\dfrac{V^2}{R}\\\\P=\dfrac{2^2}{16}\\\\=0.25\ W[/tex]

So, 0.25 W power is delivered to the bulb.

Answer:

carbon dioxide (CO2)

Explanation:

the burning or combustion of these fossil fuels creates gases that are released into the atmosphere. Of these gases, carbon dioxide (CO2) is the most common and is the gas most responsible for exacerbating the green- house effect that is changing global climate patterns.

Answer:

[tex]X=438Hz[/tex]

Explanation:

From the question we are told that:

Beat Frequency [tex]Fb=440Hz[/tex]

Actual Frequency [tex]F_a=3Hz[/tex]

Generally the equation for Frequency Heard X is mathematically given by

[tex]X=beat\ frequency\ +\ actual\ frequency[/tex]

[tex]X=F_a+Fb[/tex]

[tex]X= 440Hz+3Hz[/tex]

[tex]X=438Hz[/tex]

Answer:

According to the parallelogram law of vector addition if two vectors act along two adjacent sides of a parallelogram(having magnitude equal to the length of the sides) both pointing away from the common vertex, then the resultant is represented by the diagonal of the parallelogram passing through the same common vertex

Explanation:

Answer:

Explanation:

GPE =weight * height

       = 2000*(25-20)

      =  10000 J

Gain of Gravitation Potential energy  = 10,000 J

It is the energy acquired by an object due to a change in its position when it is present in a gravitational  field .

To calculate gravitational potential energy at height h , formula used is                                                                  =                     m g h where m = mass of the body

                                            g = acceleration due to gravity

                                            h = height from the ground

Gain of Gravitation Potential energy  = mg(h2 - h1 )      h2 = final height

                                                                             h1 = initial height

                                                = 2000  (25 -20)    (since , mg =weight)

Gain of Gravitation Potential energy  = 10,000 J

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Answer:

correct answer is c

The balls will hit the ground simultaneously

Explanation:

This is an exercise in kinematics, let's analyze each case separately

Carla. Holds the ball at an initial height y = 1,5m and releases the ball therefore its initial velocity is zero v₀ = 0

          y = y₀ + v₀ t - ½ gt²

          0 = y₀ + 0 - ½ g t²

          t = [tex]\sqrt{\frac{2y_o}{g} }[/tex]

Daniel This holds the ball at I = 1.5 m and releases the ball as it passes by Carla, therefore the initial velocity is

horizontal vox = 40 mph

vertical   v_{oy} = 0

           y = y_{oy}I + v_{oy} t - ½ g t²

            0 = y_{oy} + 0 - ½ g t²

            t = [tex]\sqrt{\frac{2 y_o}{g} }[/tex]

we can see that they both spend the same time reaching the ground

           t = [tex]\sqrt{2 \ 1.5 / 9.8}[/tex]

           t = 0.55 s

The correct answer is c

The balls will hit the ground simultaneously

Answer:

2.0km/h.

Explanation:

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Answer:

 t = 5 10² s

Explanation:

Light is an electromagnetic wave that travels at a constant speed of 3 10⁸ m/s in vacuum.

The distance from the Sun to the Earth is 150 10⁶ km

Let's reduce the distance to the SI system

       x = 150 10⁶ km (10³ m / 1 km) = 150 10⁹ m

Since the velocity is constant, we can use the uniform motion relations

       v = x / t

       t = x / v

let's calculate

       t = 150 10⁹ / 3 10⁸

       t = 5 10² s

(31-15 = 16).

Explanation:

the element phosphorus (P) has an atomic number of 15 and a mass number of 31. Therefore, an atom of phosphorus has 15 protons, 15 electrons, and 16 neutrons

Phosphorus (P) is an element with an atomic number of 15 and an atomic mass of 31, there are 16 neutrons in an atom of phosphorus, therefore the correct answer is option B

The total number of protons present in an atom is known as the atomic number of that atom. The atomic number has no correlation either with the number of neutrons or the number of electrons present inside an atom.

As given in the problem Phosphorus (P) is an element with an atomic number of 15 and an atomic mass of 31

Total number of proton in phosphorus = 15

Total number of neutrons in the phosphorus = atomic mass - atomic number

Total number of neutrons in the phosphorus =31 -15

Total number of neutrons in the phosphorus  = 16

Thus, the total number of neutrons in a phosphorus atom would be 16, therefore the correct answer is option B

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Answer: elastic potential energy

Explanation:

Answer:

Explanation:

A stretched rubber band has the potential to do work or change things. This form of energy is called elastic potential energy.