Where is the density of the material greater, at point B or point C?
Explain why.

Answer:

Explanation:

From the question we are told that

      The length of the wire is  [tex]L = 75.0cm = \frac{75}{100} = 0.75 \ m[/tex]

      The mass of the wire is  [tex]m = 2.25 \ g = \frac{2.25}{1000} = 0.00225 \ kg[/tex]

      The tension is  [tex]T = 400 \ N[/tex]        

       The frequency of the beat heard by the second student is

  [tex]f_b = 8.30\ beat/second[/tex]

The speed of the wave generated by the vibration of the wire is mathematically represented as

           [tex]v = \sqrt{\frac{TL}{m}}[/tex]

substituting values

           [tex]v = \sqrt{\frac{400 *0.75}{0.00225}}[/tex]

          [tex]v = 365.15 m/s[/tex]

         The wire is vibrating in its third harmonics so the wavelength is  

                        [tex]\lambda = \frac{2L}{3}[/tex]

substituting values

                        [tex]\lambda = \frac{2*0.75}{3}[/tex]

                        [tex]\lambda = 0.5 \ m[/tex]

The frequency of this vibration is mathematically represented as  

              [tex]f = \frac{v}{\lambda }[/tex]

substituting values  

           [tex]f = \frac{365.15}{0.5 }[/tex]

          [tex]f = 730.3 Hz[/tex]

The speed of the second student (Observer) is mathematically represented as

           [tex]v_o = [\frac{f_b}{2f} ] * v[/tex]

substituting values    

         [tex]v_o = [\frac{8.30}{2* 730.3} ] * 365.15[/tex]

        [tex]v_o = 2.08 \ m/s[/tex]

Answer:

R = 73.25 m

Explanation:

We have,

Initial speed of the ball is 27 m/s

It is projected at an angle of 40 degrees

The maximum range of the ball is given by :

[tex]R=\dfrac{u^2\sin2\theta}{g}[/tex]

Plugging all the values we get :

[tex]R=\dfrac{(27)^2\sin2(40)}{9.8}\\R=73.25\ m[/tex]

So, the maximum range of the ball is 73.25 m

Explanation:

a) 120m

b) since Q is the first order constructive interference, the distance between mid point of antennas and Q is 0.5 wavelengths (appear in A-Level question). so the wavelength should be (2)(30) =60m

60m

Answer:

44.4m/s

Explanation:

v = (3.7*10 ^3) ( 1.2 * 10 ^ -2)

= 44.4 m/s

Answer:

44.4 m/s

Explanation:

By using the wave speed formula, v = fλ ( speed= frequency × wavelength)

v = 3.7×10³ × 1.2×10^-2

= 44.4 m/s

Hope that's the answer you're looking for:)

Answer:

Light when strikes mirror, it bounces off where as it transmits through a lens. A mirror is glass with lustrous metal coated at its back. Light reflects off a mirror and image is formed behind it.

Explanation:

So the right answer is 0.98 watt.

look at the attached picture

Hope it will help you

Answer:

Option C. is correct

Explanation:

The magnetic field is the area around a magnet in which there is magnetic force. When an electric current flows through a wire a  magnetic field is created. A single wire does not produce a strong magnetic field. So, to increase the power  of the magnetic field, increase the number of coils in the wire.

Answer:

[tex]v = \sqrt{16\cdot g \cdot L}[/tex]

Explanation:

The physical phenomenon is described by the Principles of Momentum Conservation and Energy Conservation:

Momentum

[tex]m \cdot v = M\cdot \frac{v}{2} + m \cdot v'[/tex]

Energy

[tex]\frac{1}{2}\cdot m \cdot v^{2} = \frac{1}{8}\cdot M \cdot v^{2} + \frac{1}{2}\cdot m \cdot v'^{2}[/tex]

[tex]\frac{1}{8}\cdot M\cdot v^{2} = 2\cdot M\cdot g \cdot L[/tex]

The minimum speed of the pendulum bob so that it could barely swing through a complete vertical cycle is:

[tex]\frac{1}{8}\cdot v^{2} = 2\cdot g\cdot L[/tex]

[tex]v^{2} = 16\cdot g\cdot L[/tex]

[tex]v = \sqrt{16\cdot g \cdot L}[/tex]

Answer:

Explanation:

Moment of inertia of each wheel = 1/2 m R²

m is mass and R is radius of wheel

= .5 x 15.5 x .175²

= .2373 kg m²

moment of inertia of tyre

1/2 m ( r₁² + r₂² )

= 1/2 x 1.9 x ( .315² + .19²)

= 1/2 x 1.9 x ( .099+ .036)

= .12825 kg m²

moment of inertia of tread

= 1/2 m r²

= .5 x 12 x .335²

= .67335 kg m²

moment of inertia of axle

= 1/2 m r ²

= .5 x 14.5 x .0195²

= .00275

moment of inertia of drive shaft

= 1/2 x 32.5 x .029²

= .0137 kg m ²

Total moment of inertia of one tyre

=  1.05535 kg m²

total moment of inertia of two rear wheels

= 2.1107 kg m²

95 % of torque

= .95 x 180

= 171 Nm

angular acceleration

= torque / moment of inertia

= 171 / 2.1107

= 81.01 radian /s²

Answer:

launching speed of the lighter block = -6 m/s

Explanation:

We are given;

Mass of light block; M

Mass of heavy block; 3M

Speed of launched block: v = 2m/s

We are told that the two blocks are sitting on the horizontal frictionless surface. Thus, we can say that no external force is being applied on the system and so, the momentum of the whole system is conserved accordingly to that condition.

We are also told that when the rope is cut with scissors, that the heavier block attains the speed of 2 m/s in the positive x-direction which is horizontal direction.

We know that formula for momentum is; M = mass x velocity.

Thus, the momentum of the heavier block is calculated as;

M_1 = 3M × 2

M_1 = 6M kg.m/s

Since no external force is applied on the object, the initial momentum will be zero.

Hence, to conserve the system, the momentum of the lighter block will be equal and opposite to the momentum of heavier block.

So, momentum of lighter block is;

M_2 = -6M kg.m/s

Since mass of lighter block is M and formula for momentum = mass x velocity.

Thus;

-6M = Mv

Where v is speed of lighter block.

So, v = -6M/M

v = -6 m/s

Answer:

The percentage of an iceberg submerged beneath the surface of the ocean = 89.67%

Explanation:

Let V be the total volume of the iceberg

Let x be the volume of iceberg submerged

According to Archimedes principle,

weight of the iceberg = weight of the water displaced (that is, weight of x volume of water)

Weight of the iceberg = mg= ρ(iceberg) × V × g

Weight of water displaced = ρ(fluid) × x × g

We then have

ρ(iceberg) × V × g = ρ(fluid) × x × g

(x/V) = ρ(iceberg) ÷ ρ(fluid) = 916.3 ÷ 1021.9 = 0.8967 = 89.67%

Hope this Helps!!!!

Answer:

Explanation:

The y component is measured by the horizontal component and the vertical component. Together they determine the magnitude of the vector. In this case, the y or vertical component is found by using the sine function.

Formula

Sin(angle) = vector resultant / y component component.

Givens

angle = 42 degrees.

vector = 419 degrees

Solution

sin(42) = y / 419                  Multiply both sides by 419

419 * sin(42) = 419  * y / 419

y = 419 * 0.6691

y = 280.37

Note

The vector is pointing downward so technically the vertical component should be negative.  I'm not sure what to tell you to answer. I would try - 280.37, but if the computer marks you wrong, try 280.37 (no minus sign).

Answer:

a) -1529m

b)-1326m

c)268.84 meters.

Explanation:

a) Since the stone is thrown horizontally, its initial vertical velocity is the same as the basket. Let’s use the following equation to determine the vertical distance it moves in 18.8 seconds.

According to kinematic equation the displacement is given by

[tex]h_1 = v_{0y} y - \frac{1}{2}gt^2[/tex]

[tex]h_1[/tex]=10.8 * 18.8 -  ½ * 9.8 * 18.8² => -1529m

The negative sign is due to the direction.

b)while the stone was travelling [tex]h_1[/tex] for 18.8s the balloon was also travelling the displacement [tex]h_b[/tex] with [tex]v_o_y[/tex]. so [tex]h_b[/tex]  is given by

[tex]h_b=v_o_y t= - 10.8\times18.8[/tex]=> -203.04m

The height above the eart is given by,

[tex]h_2=h_1-h_b = -1529+203.04 => -1326[/tex]m

c)At the instant the rock hits the ground, how far is it from the basket?  

This is the product of its initial horizontal velocity and the time.

d = 14.3 * 18.8 = 268.84 meters.

Answer:

a. Valid

b. Invalid

c. Invalid

d. Invalid

e. Valid

f.  Valid

g. Invalid

Explanation:

a.

Since, it follows all the four rules,

Therefore, this number is Valid

b.

It uses upper case E, instead of lower case e.

Therefore, it is Invalid

c.

It violates third rule for including unit.

Therefore, it is Invalid

d.

It violates the first rule. As, there is a space between 6 and e. While in the example given in question, there is no gap.

Therefore, it is Invalid

e.

Since, it follows all the four rules,

Therefore, this number is Valid

f.

Since, it follows all the four rules,

Therefore, this number is Valid

g.

It violates third rule for including unit.

Therefore, it is Invalid

Answer:

Explanation:

Force of friction

F = μ mg

μ is coefficient of friction , m is mass and g is acceleration due to gravity .

If f be the force applied to pull the sled , the horizontal component of force should be equal to frictional  force

The vertical component of applied force will reduce the normal force or reaction force from the ground

Reaction force R = mg - f sin28.3

frictional force = μ R where μ is coefficient of friction

frictional force = μ x (mg - f sin28.3 )

This force should be equal to horizontal component of f

μ x (mg - f sin28.3 ) = f cos 28.3

μ x mg = f μsin28.3 + f cos 28.3

f = μ x mg / (μsin28.3 + cos 28.3 )

a )

work done by pulling force  = force x displacement

f cos28.3 x d

μ x mg d cos28.3  / (μsin28.3 + cos 28.3 )

b ) Putting the given values

= .155 x 53.1 x 9.8 x 25.3 cos28.3 / ( .155 x sin28.3 + cos 28.3 )

= 1796.76 / (.073 + .88 )

= 1885.37  J

c )

Work done by frictional force

= frictional force x displacement

=  -  μ x (mg - f sin28.3 ) x d  

= -  μ x mgd + f μsin28.3  x d

= -  μ x mgd + μsin28.3  x d x μ x mg / (μsin28.3 + cos 28.3 )

d )

Putting the values in the equation above

- .155 x 53.1 x 9.8 x 25.3 +

.155 x .474 x 25.3 x .155 x 53.1 x 9.8 /( .155 x .474 + .88)

= -2040.67 + 149.92 / .95347

= -2040.67 + 157.23

= -1883.44 J .

Answer:

a. lower surface area, less resistence

b. more surface area, the load is split so no single tire overstrained

c. more surface area, more resistance against the sand. human steps sink down in the sand.

d. rapid change in air pressure on eardrums lead to somewhat-painful tension

e. air would always find its way in so no pressure difference can be achieved

(would indeed appreciate the brainliest if you appreciate the work)

Answer:

A) 3

B) fraction is 2/1 = 2

C) 3 C

Explanation:

Initial capacitance with air U is 3 C

Final charge with dielectric Ud material is 9 C

Dielectric constant = capacitance with dielectric/capacitance with air

= 9/3 = 3

Since it is connected to a battery, the potential difference at the plate will be constant.

P.d = V

Also energy stored in a capacitor is given as 0.5CV^2

For capacitance with air, energy is 0.5 x 3 x V^2 = 9V^2

For capacitance with dielectric, energy is 0.5 x 9 x V^2 = 18V^2

Fraction of energy stored in capacitance with dielectric to that with air is 18V^2/9V^2 = 2

From C = eA/d

Where C is the capacitance,

e is the dielectric constant

A is the area of the dielectric

d is the distance between plates of the capacitor.

For initial, assuming the distance to be of unit distance, area will be given as

9 = (3 x A)/1

9 = 3A

A = 2 m^2. If we pull dielectric half way out, area becomes

C = (3 x 1)/1

C = 3 C

Answer:

The ball stops due to friction when it rolls on something such as grass.

Explanation:

Newton's first law is that an object will move at a constant velocity or stay at rest, unless it is acted upon by an external force.

When a ball on Earth is kicked or rolled, it is subject to external forces that oppose it's motion (like the force due to gravity and air resistance, or friction when rolling on the ground) - so the ball will not keep moving and will eventually stop.

Complete Question

The complete question is shown on the first uploaded image  

Answer:

The expression for the change in the air temperature is   [tex]\Delta T = \frac{Mv^2}{2 \rho_{air} c_{air}* V}[/tex]

Explanation:

From the question we are told  that

     The mass of the train is  M

     The speed of the train is  v

     The volume of the station is  V

      The density of air in the station is  [tex]\rho_{air}[/tex]

       The specific heat of air is  [tex]c_{air}[/tex]

The workdone by the break can be mathematically represented as

         [tex]W =\Delta KE = \frac{1}{2} Mv^2[/tex]

Now this is equivalent to the heat  transferred to air in the station

   Now the heat capacity of the air in the station is mathematically represented as

          [tex]Q = \rho_{air} * m_{air} * c_{air} (\Delta T)[/tex]

Now Since this is equivalent to the workdone by the breaks we have that

         [tex]\frac{1}{2} Mv^2 = m_{air} * c_{air} (\Delta T)[/tex]

=>     [tex]\Delta T = \frac{Mv^2}{2 \rho_{air} c_{air}* V}[/tex]

Answer:

a

The  radial acceleration is  [tex]a_c = 0.9574 m/s^2[/tex]

b

The horizontal Tension is  [tex]T_x = 0.3294 i \ N[/tex]

The vertical Tension is  [tex]T_y =3.3712 j \ N[/tex]

Explanation:

The diagram illustrating this is shown on the first uploaded

From the question we are told that

   The length of the string is  [tex]L = 10.7 \ cm = 0.107 \ m[/tex]

     The mass of the bob is  [tex]m = 0.344 \ kg[/tex]

     The angle made  by the string is  [tex]\theta = 5.58^o[/tex]

The centripetal force acting on the bob is mathematically represented as

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

Now From the diagram we see that this force is equivalent to

     [tex]F = Tsin \theta[/tex] where T is the tension on the rope  and v is the linear velocity  

     So

          [tex]Tsin \theta = \frac{mv^2}{r}[/tex]

Now the downward normal force acting on the bob is  mathematically represented as

          [tex]Tcos \theta = mg[/tex]

So

       [tex]\frac{Tsin \ttheta }{Tcos \theta } = \frac{\frac{mv^2}{r} }{mg}[/tex]

=>    [tex]tan \theta = \frac{v^2}{rg}[/tex]

=>   [tex]g tan \theta = \frac{v^2}{r}[/tex]

The centripetal acceleration which the same as the radial acceleration  of the bob is mathematically represented as

      [tex]a_c = \frac{v^2}{r}[/tex]

=>  [tex]a_c = gtan \theta[/tex]

substituting values

     [tex]a_c = 9.8 * tan (5.58)[/tex]

     [tex]a_c = 0.9574 m/s^2[/tex]

The horizontal component is mathematically represented as

     [tex]T_x = Tsin \theta = ma_c[/tex]

substituting value

   [tex]T_x = 0.344 * 0.9574[/tex]

    [tex]T_x = 0.3294 \ N[/tex]

The vertical component of  tension is  

    [tex]T_y = T \ cos \theta = mg[/tex]

substituting value

     [tex]T_ y = 0.344 * 9.8[/tex]

      [tex]T_ y = 3.2712 \ N[/tex]

The vector representation of the T in term is of the tension on the horizontal and the tension on the vertical is  

       [tex]T = T_x i + T_y j[/tex]

substituting value  

      [tex]T = [(0.3294) i + (3.3712)j ] \ N[/tex]

The radical acceleration of the bob is 0.9575 m/s². The horizontal and vertical components of the tension force exerted by the string on the bob are 0.329 N and 3.37 N respectively.

Taking the vertical component of the tension where the weight mass is balanced, then:

T sin θ = mg

[tex]\mathbf{T = \dfrac{mg}{sin \theta}}[/tex]

However, the centripetal force of the system is given by the horizontal component of the tension which can be expressed as:

T cos θ = m[tex]\mathbf{a_r}[/tex]

Making [tex]\mathbf{a_r}[/tex] the subject, we have:

[tex]\mathbf{a_r = \dfrac{Tcos \theta }{m}}[/tex]

replacing the value of tension (T), we have:

[tex]\mathbf{a_r = \dfrac{ \dfrac{mg}{sin \theta}cos \theta }{m}}[/tex]

[tex]\mathbf{a_r=g tan \theta}[/tex]

where;

[tex]\mathbf{a_r=9.8 m/s^2 \times tan 5.58}[/tex]

[tex]\mathbf{a_r=9.8 m/s^2 \times 0.0977}[/tex]

[tex]\mathbf{a_r=0.9575 \ m/s^2}[/tex]

Thus, the radical acceleration of the bob is 0.9577 m/s²

On the positive x-axis, the horizontal component of the tension force is:

[tex]\mathbf{T_x =Tcos \theta}[/tex]

[tex]\mathbf{T_x =ma_r}[/tex]

[tex]\mathbf{T_x =0.344 \ kg \times 0.9575 \ m/s^2}[/tex]

[tex]\mathbf{T_x =0.329 \ N}[/tex]

On the positive y-axis, the vertical component of the tension force is:

[tex]\mathbf{T_y =Tsin \theta}[/tex]

[tex]\mathbf{T_y =mg}[/tex]

[tex]\mathbf{T_y=0.344 \ kg \times 9.8 \ m/s^2}[/tex]

[tex]\mathbf{T_x =3.37 \ N}[/tex]

Learn more about simple pendulum here:

https://brainly.com/question/12886217?referrer=searchResults

Answer:  D i think

Explanation:

Answer:

Acceleration, [tex]a=2\ m/s^2[/tex]

Explanation:

We have,

Initial speed of an object is 30 m/s

It accelerates to a velocity of 55 m/s over a time of 12.5 s

It is required to find the acceleration experienced by it. The rate of change of velocity is called acceleration of an object. It is given by :

[tex]a=\dfrac{v-u}{t}\\\\a=\dfrac{55-30}{12.5}\\\\a=2\ m/s^2[/tex]

So, the acceleration of the object is [tex]2\ m/s^2[/tex].

Answer:

D.

all of these.......

Answer:

Radius, r is equal to 229.16×10^6m

Explanation:

Given the following parameters;

Centripetal force on the satellite, Fc = 190N.

Mass of the satellite, M = 1,550-kg.

Speed of the satellite, V = 5,300m/s.

The relationship between a satellite of mass (m) moving in a circular orbit of radius (r) with a speed (v) and a centripetal force (Fc) is given by the equation;

Fc = (MV²)/r

Since, we're solving radius, r; we make "r" the subject of formula;

Thus, r = (MV²)/Fc

Substituting into the above equation;

r = (1550 × [5300]²)/190

r = (1550 × 28090000)/190

r = 43539500000/190

r = 229155263.16

Radius, r is equal to 229.16 × 10^6m

Explanation:

They will repel, thus made of electrical conductor.

Answer:

1.000153 T

Explanation:

The energy change ΔE = hc(1/λb - 1/λa)

= 6.626069 ✕ 10⁻³⁴ J · s 2.997925 × 10⁸ m/s(1/6.544750 × 10⁻⁷ m - 1/6.544550 × 10⁻⁷ m)

= 19.864457907 × 10⁻²⁶(1527942.2438 - 1527988.9374) = 19.864457907 × 10⁻²⁶(-46.6936)

= 927.543052 × 10⁻²⁶

= -9.275431× 10⁻²⁴ J.

This energy change ΔE = 2μBB. So the magnetic field, B is

B = ΔE/2μB where μB = 9.274009 ✕ 10⁻²⁴ J/T

B = -9.275431× 10⁻²⁴ J/9.274009 ✕ 10⁻²⁴ J/T = -1.000153 T

The magnitude of the magnetic field B = 1.000153 T

Answer:

When objects fall to the ground, gravity causes them to accelerate.

Explanation:

Gravity causes an object to fall toward the ground at a faster and faster velocity the longer the object falls.

XL = 2π•f•L = 86.7 ohms