A swimmer heads for the opposite bank of a river. Make a sketch showing the swimmer's two velocities and the resultant velocity. (Assume the river flows in the +x direction and the opposite bank is in the +y direction.)

Answer:

Using sold paper is better than to burn it because burning paper may cause pollution.

Explanation:

Hope it will help ^_^

Answer:

Let's take the frequency receive by police officer to be

f¹/f²= u-v/u+v

So 1255/1205= 340-v/340+v

V= 6.9m/s positive value implies that the car is moving toward the police

2 to find frequency we use

f/1205= 340+25/340-25

f= 1396Hz

Answer:

B.  The brain moves inside the skull with a force equal and opposite to that of the impact.

Explanation:

Just took the test and got it correct.

Applying Newton's laws the brain is in danger of injury when an impact is made to our head because ; ( B ) The brain moves inside the skull with a force equal and opposite to that of the impact

According to Newton's law an object will continue to be at rest except a force ( impact ) acts on it. also the third law of Newton states that when two objects interact ( The brain and the impact to the head ) they apply forces of equal magnitude to each other but in opposite directions from one another.

The Impact to the head will have a direct effect on the brain because the brain will move in opposite direction to the direction of the impact and with the same magnitude which will lead to an injury to the brain because the brain is suppose to be at rest at all times and not in motion.

Hence we can conclude that Applying Newton's laws the brain is in danger of injury when an impact is made to our head because The brain moves inside the skull with a force equal and opposite to that of the impact.

Learn more : https://brainly.com/question/13532462

Your question has been heard loud and clear.

Averge velocity formula=  Total distance travelled / total time taken.

Total distance=7meters

Total time taken=9 seconds.

Average velocity = 7/9= 0.77 metres/second

Average velocity= 0.77m/s

Thank you.

Answer:

W = 5000 J

Explanation:

Weight hold by a weightlifter is 1700 N, 1 meter above the ground.

One end of a 2-meter-long chain hangs from the center of the barbell. The chain has a total weight of 800 N.

We need to find the work is required to lift the barbell to a height of 2 m.

Total force is : 1700 N + 800 N = 2500 N

Work done in Physics is given by :

W = F×d

So,

W = 2500 N × 2 m

W = 5000 J

Hence, 5000 J of work is required to lift the barbell to a height of 2 m.

Answer:

Here are some of the main cons of nuclear energy.

•Expensive to Build. Despite being relatively inexpensive to operate, nuclear power plants are incredibly expensive to build—and the cost keeps rising. ...

•Accidents. ...

•Produces Radioactive Waste. ...

•Impact on the Environment. ...

•Security Threat. ...

•Limited Fuel Supply.

[tex]\huge\underline\mathcal\pink{Answer:-}[/tex]

The nuclei of atoms contain a large amount of energy. Releasing this energy would free the world from having to use fossil fuels. There are two methods of doing this: fission and fusion.

1. Nuclear is a bad match for renewables.

2. Building nuclear power stations is very expensive.

3.There are huge costs beyond simply constructing the power stations.

4 Nuclear power stations take at least a decade to build.

[tex]\huge\red{kya \: aap \: samajhe?}[/tex]

Answer:

5m/s²

Explanation:

v²-v¹ =50 - 25 = 25m/s = 5m/s²

t 5 5

Answer:

Following are the answer to this question:

Explanation:

Galileo claims that perhaps the air resistance is due to an object falling slower. The object gradually falls under its control of free-fall gravity.  

A free-falling object is also an object, which is affected by gravity only. The object operated only by the gravitational force is considered to get into a condition of free fall and the Items, that fall free may not feel air resistance.

please find the attachment.

Answer:

5 N

Explanation:

From the question,

The magnitude of the force that would be required to just loosen the nut when the force is applied perpendicularly at the end of the handle is

Fy = Fsinθ................. Equation 1

Where Fy = force acting perpendicular at the end of the handle, F = Force applied to the handle, θ = angle of inclination of the force to the end of the handle.

Given: F = 10 N, θ = 30°

Substitute these values into equation 1

Fy = 10(sn30°)

Fy = 10(0.5)

Fy = 5 N.

Complete Question

A thin, horizontal, 12-cm-diameter copper plate is charged to 4.4 nC . Assume that the electrons are uniformly distributed on the surface. What is the strength of the electric field 0.1 mm above the center of the top surface of the plate?

Answer:

The  values is  [tex]E =248.2 \ N/C[/tex]

Explanation:

From the question we are told that

   The  diameter is  [tex]d = 12 \ cm = 0.12 \ m[/tex]

    The charge  is  [tex]Q = 4.4 nC = 4.4 *10^{-9} \ C[/tex]

    The  distance from the center  is  [tex]k = 0.1 \ mm = 1*10^{-4} \ m[/tex]

Generally the radius is mathematically represented as

        [tex]r = \frac{d}{2}[/tex]

=>     [tex]r = \frac{0.12}{2}[/tex]

=>       [tex]r = 0.06 \ m[/tex]

Generally electric field is mathematically represented as  

       [tex]E = \frac{Q}{ 2\epsilon_o } [1 - \frac{k}{\sqrt{r^2 + k^2 } } ][/tex]

substituting values  

      [tex]E = \frac{4.4 *10^{-9}}{ 2* (8.85*10^{-12}) } [1 - \frac{(1.00 *10^{-4})}{\sqrt{(0.06)^2 + (1.0*10^{-4})^2 } } ][/tex]

     [tex]E =248.2 \ N/C[/tex]

Answer this question

Explanation:

Answer:

2.3*10^8m/s

Explanation:

Using

V = c/n

Where c= speed of light

n = refractive index of water

By substituting

We have

V= 3*10^8m/s/1.33

= 2.3*10^8m/s

Answer:

A) 10.243 s

B) 514.64 m

C) 153.645 m

Explanation:

From projectile motion;

y(t) = h - ½gt²

Where;

h is the height of cliff

t is the time taken to fall from top of cliff down to half the height of the cliff

y(t) is height of the rock as function of time

We are told the rock falls half way of the cliff height.

Thus;

y = h/2

So;

h/2 = h - ½gt²

This gives;

h - h/2 = ½gt²

h/2 = ½gt²

h = gt² - - - - (1)

Also,the total free fall time from top of the cliff to ground would be;

T = t + 3

Thus, distance at this point is zero.

So;

0 = h - ½gT²

h = ½gT²

Putting t + 3 for T, we have;

h = (1/2)g(t + 3)² - - - 2

Inspecting eq 1 and eq 2,we have;

gt² = (1/2)g(t + 3)²

g will cancel out to give;

2t² = t² + 6t + 9

t² - 6t - 9 = 0

The roots are -1.243 or 7.243.

We will pick the positive value as time can't be negative.

Thus, T = 7.243 + 3 = 10.243 s

h = gt² = 9.81 × 7.243²

h = 514.64 m

Formula for horizontal distance is given by;

x = uT

Where u is initial speed given as;

u = 15 m/s

Thus;

x = 15 × 10.243

x = 153.645 m

Answer:

1319.14 lb

Explanation:

From the question above,

Density of the Blazblue extract = mass of Blazblue extract/volume of Blazblue extract.

D = m/v.............. Equation 1

make m the subject of the equation

m = D×v.................... Equation 2

Given: D = 0.770 grams per millilitre, v = 29053 liters = 29053000 millilitres

Substitute these values into equation 2

m = 0.770×29053000

m = 22370810 grams

If,

1 gram = 0.00220462 pounds,

Then,

22370810 grams = (22370810×0.00220462) = 41319.14 lb

Answer:

The  value is  [tex]g =  16.104 \  m/s[/tex]

Explanation:

From the question we are told that

 The  length is  [tex]l = 53.0 \ cm = 0.53 \ m[/tex]

 The  number of cycle is  [tex]n = 105[/tex]

  The time taken is  [tex]t = 125 \ s[/tex]

The period is mathematically represented as

    [tex]T  =  2 \pi \sqrt{\frac{ l}{g} }[/tex]

Also the period is mathematically represented as

      [tex]T    =  \frac{ t}{n}[/tex]

      [tex]T  =  \frac{125}{110}[/tex]

      [tex]T  =  1.14 \ s/cycle[/tex]

So

      [tex]1.14  =  2 * 3.142  \sqrt{\frac{ 0.53}{g} }[/tex]

=>   [tex]g =  \frac{ 4 *  3.142^2 *  0.53}{1.14^2}[/tex]

=>     [tex]g =  16.104 \  m/s[/tex]

Answer:

[tex] \boxed{\sf Tension \ in \ the \ string \ (T) = 3 \ kN} [/tex]

Given:

Mass (m) = 3.0 kg

Uniform speed (v) = 20 m/s

Length of string (r) = 40 cm = 0.4 m

To Find:

Tension in the string (T)

Explanation:

Tension (T) is the string will be equal to centripetal force ([tex] \sf F_c [/tex]).

[tex] \boxed{ \bold{ T = F_c = \frac{m {v}^{2} }{r} }}[/tex]

Substituting value of m, v & r in the equation:

[tex] \sf \implies T = \frac{3 \times {20}^{2} }{0.4} \\ \\ \sf \implies T = \frac{3 \times 400}{0.4} \\ \\ \sf \implies T =3 \times 1000 \\ \\ \sf \implies T =3000 \: N \\ \\ \sf \implies T =3 \: kN[/tex]

[tex] \therefore[/tex]

Tension in the string (T) = 3 kN

Answer:  C. the motion of a spacecraft under gravitational influence.

Explanation:

A is Metallurgy, B is Biology, C is astro-physics, I am not sure what D is, but it's   safe to say it's not physics, E, micro-biology, and the study of radiation. C is the only one involving physics.

Here ,

• Height of sign post = 30 m

• Distance between signpost and truck = 24 m

Let the

• Top of signpost = A

• Bottom of signpost = B

• The end of truck facing sign post be = C

Now as we can clearly imagine that the ladder will act as an hypotenuse to the Triangle ABC .

Where

• AB = Height of signpost = 30 m

• BC = distance between both = 24 m

• AC = Minimum length of ladder

→ AC² = AB² + BC² ( As we can see AB is perpendicular to BC )

→ AC² = (30)² + (24)²

→ AC² = 900 + 576

→ AC² = 1476

→ AC = 38.41875

or AC apx = 38.42

So minimum height of ladder = 38.42

This question can be solved by using the formula of "Pythagora's Theorem".

The ladder must be "38.42 m" long.

If we imagine the whole situation in terms of a right-angled triangle, we can safely assume the height of the billboard (which is the pole supporting the billboard) as the perpendicular of the right-angled triangle. The distance between the signpost and the truck can be assumed as the base of the triangle. The length of the ladder will then be acting as the Hypotenuse of the right-angled triangle.

The attached picture clearly depicts the condition explained in the above paragraph.

Now applying Pythagora's Theorem to this situation, we get:

[tex]Hypotenuse^2 = Perpendicular^2+Base^2\\Length\ of\ Ladder^2 = (30\ m)^2+(24\ m)^2\\L^2 = 1476\ m^2\\[/tex]

L = 38.42 m

Learn more about Pythagora's Theorem here:

https://brainly.com/question/343682?referrer=searchResults

Answer:

Volume flow rate = [tex]1.41 \times 10^{-3}m^3/s[/tex]

Explanation:

The volume flow rate through a channel can be gotten by multiplying its area and its velocity.

The channel under consideration is a circular channel. Hence, the cross-sectional area can be calculated by using the relation for calculating the area of a circle

Cross-sectional area = [tex]\pi \times d^{2}/4[/tex]

[tex]A = \pi \times (3\times 10^-2)^2 /4 = 7.07 \times 10 ^-4 m^2[/tex]

volume flow rate= [tex]A = 7.07 \times 10 ^-4 m^2 X 2.0 = 1.41 \times 10^{-3}m^3/s[/tex]

Volume flow rate = [tex]1.41 \times 10^{-3}m^3/s[/tex]

Answer:

1) Only the perpendicular component of wind is responsible for the rotation, because gravity points downward.

2) static friction is greater than kinetic friction and the applied force acts oppositely

3)   Inertia decreases with decreasing radius of the orbit.

4) constant is the mass of the car

Explanation:

1) In order to know which statement is correct, let's analyze the movement of the mill.

The rotation of the blades due to a force perpendicular to each one, which creates a torque that results in its rotation.

The true force does not affect the movement because it is applied at the center of mass of the mill that coincides with its axis of rotation.

Of the statements, the correct one is:

The perpendicular to the wind is responsible for the movement

2) static friction is the result of microscopic bonds between two surfaces when there is no relative motion between them

kinetic friction is the result of the unions between the two surfaces when there is a relative movement between them.

From these statements it follows that friction is contrary to motion, static friction must be greater than kinetic friction.

Of the statements the correct one is:

static friction is greater than kinetic friction and the applied force acts oppositely

3) The inertia of a particle is

         I = m R²

where m is the mass of the satellite and R is the distance from the center of the Earth, decreasing with each orbit

The correct answer is:

  Inertia decreases with decreasing radius of the orbit.

4) From the figure it can be seen that the motorist subjected to a constant force, for which we can apply Newton's second law

          F = m a

The force equals the applied weight.

The quantity that is held constant is the mass of the car

since the applied force and therefore the acceleration can be changed by changing the applied weight.

Answer:

1. The perpendicular components of gravity and the force of wind are responsible for the rotation.  

2. Static friction is greater than kinetic friction, but they both act opposite the applied force.

3. Rotational inertia decreases proportional to the decrease in the radius of rotation.

4. mass

Answer:

provide new testble ideas

Answer:

The wavelength of the emitted photon is 413.6 nm

Explanation:

Given;

energy of the emitted photon, E = 3 eV = 3 x 1.602 x 10⁻¹⁹ J

speed of light, c  = 3 x 10⁸ m/s

The energy of the emitted photon is given by;

E = hf

where;

h is Planck's constant = 6.626 x 10⁻³⁴ J/s

f is the frequency of the light = c / λ

λ is the wavelength

[tex]E = \frac{hc}{\lambda}\\\\\lambda = \frac{hc}{E}\\\\\lambda = \frac{(6.626*10^{-34})(3*10^8)}{3*1.602*10^{-19}}\\\\\lambda = 4.136 *10^{-7} \ m\\\\\lambda = 413.6 *10^{-9} \ m\\\\\lambda = 413.6 \ nm[/tex]

Therefore, the wavelength of the emitted photon is 413.6 nm

Explanation:

When light travels from air into water, due to the change in refractive index of the two medium, refraction of light occurs.

Velocity of light in a medium is given by :

[tex]v=\dfrac{c}{n}[/tex]

c is speed of light

n is refractive index

The frequency remains the same in every medium. It means that the its velocity and wavelength change, but its frequency does not change.

Answer:

The first graph is showing the constant acceleration (1 m/s)

Explanation:

The second graph showing the flexible velocity therefore a in the graph is different at t1, t2, t3, t4

The last graph is showing constant velocity therefore there is no acceleration (a = 0)

Answer:

A

Explanation:

on edge

Answer:

Explanation:

 |F-->1| =  E-->1 x charge on proton

= 300 x 1.6 x 10⁻¹⁹

Magnitude of electric force on proton

|F-->1| = 480 x 10⁻¹⁹ N .

Inside lithium nucleus , there are three protons so charge on it

= 3 x 1.6 x 10⁻¹⁹ = 4.8 x 10⁻¹⁹ C .

Magnitude of electric force on lithium nucleus

|F-->Li|  =   E-->1 x charge on lithium nucleus

= 300 x  4.8 x 10⁻¹⁹

= 1440 x 10⁻¹⁹ N .

Electron has same charge as that possessed by proton so charge on electron = 1.6 x 10⁻¹⁹ C

Magnitude of force on electron

|F-->1| =  E-->1 x charge on electron

= 300 x 1.6 x 10⁻¹⁹

=  480 x 10⁻¹⁹ N .

Answer:

The average velocity is 180 km/hr

Explanation:

Given;

initial velocity, u = 60 km per hour

final velocity, v = 120 km per hour

initial time = 1 hour

final time = 2 hour

Initial position = 60 km/h x 1 hour = 60 km

final position = 120 km/h x 2 hour = 240 km

The average velocity is given by;

[tex]V_{avg} = \frac{Final \ position\ - \ Initial \ position}{final \ time\ - \ initial \ time}\\\\V_{avg} = \frac{240km \ - \ 60km}{2hr\ - \ 1hr} \\\\V_{avg} = \frac{180 \ km}{1hr} \\\\V_{avg}= 180 \ km/hr[/tex]

Therefore, the average velocity is 180 km/hr

Complete Question

A grating has 767 lines per centimetre.Find the angles of the first three principal maxima above the central fringe when this grating is illuminated with 672 nm light.

Answer:

The  first is  

      [tex]\theta_1 = 2.92^o[/tex]

 The second is  

       [tex]\theta _2 = 5.93^o[/tex]

 The third is  

        [tex]\theta _3 = 8.92^o[/tex]

Explanation:

From the question we are told that

        The  number of lines per cm is  [tex]I = 767 \ lines/cm = 76700 \ lines / m[/tex]

        The  wavelength is  [tex]\lambda = 672nm = 672 *10^{-9} \ m[/tex]

Generally the condition for constructive  interference is  

            [tex]dsin (\theta ) = n\lambda[/tex]    

Here d is the distance of separation of the slit which is mathematically represented as

             [tex]d = \frac{1}{l}[/tex]

             [tex]d = \frac{1}{76700}[/tex]

             [tex]d = 1.30*10^{-5} \ m[/tex]

So          

           [tex]\theta_1 = sin^{-1} [\frac{ n \lambda }{ d} ][/tex]

For the  first angle  n =  1  

  So  

        [tex]\theta_1 = sin^{-1} [\frac{ 1 * 672 *10^{-9} }{ 1.30 *10^{-5}} ][/tex]

          [tex]\theta_1 = 2.92^o[/tex]

For  the second angle  n  =  2

      So  

            [tex]\theta_2 = sin^{-1} [\frac{ 2 * 672 *10^{-9} }{ 1.30 *10^{-5}} ][/tex]

            [tex]\theta _2 = 5.93^o[/tex]

For  the second angle  n  =  3

      So  

           [tex]\theta_3 = sin^{-1} [\frac{ 3 * 672 *10^{-9} }{ 1.30 *10^{-5}} ][/tex]

          [tex]\theta _3 = 8.92^o[/tex]

84km/hr

Explanation:

To find one light yr

= 3E8m/s x 24x 365/1000

= 996980E7kms

So

Radius of orbit for 24000light years

=996980E7kms x 24000

Total orbit distance is = 2πr

= 2 *π x 996980E7kms x 24000

Total time will be

= 194E6 x 24x365 hrs

Finally speed = distance/ time

= 2 *π x 996980E7kms x 24000/194E6 x 24x365 hrs

= 84km/hr

Answer:

yes it would.

Explanation:

Answer:

t = log9/10 x RC

Explanation:

Let's say initial energy is

E= 1/2Q²/C

But if 90% is discharged what will be remaining will be

E= E"/100= 1/2Q²/C

So if we divide the first by the second equation we have

Q'= Q/10

Then using

q=q0(1-e^-t /RC)

So that

Q= Q/10(1-e^-t /RC)

t/RC= log9/10

So t = log9/10 x RC