A 0.1 kg arrow with an initial velocity of 30 m/s hits a 4.0 kg melon initially at rest on a friction-less surface. The arrow emerges out the other side of the melon with a speed of 20 m/s. What is the speed of the melon? Why would we normally not expect to see the melon move with the is speed after being hit by the arrow?​

Answers

Answer 1

Answer:

Speed of the melon = 0.25 m/s

we would normally don't see the melon moving due to friction with the resting surface.

Explanation:

We use conservation of momentum:

Pi = Pf

with Pi = 0.1 kg * 30 m/s = 3 kg m/s

and Pf = 0.1 kg * 20 m/s + 4.0 kg * V = 2 kg m/s + 4 * V

Then using the equality above, we solve for V (velocity of the melon)

3 kg m/s = 2 kg m/s + 4 V

1 kg m/s = 4 kg * V

Then V = 1 / 4  M/s = 0.25 m/s

So we would normally don't see the melon moving due to friction with the resting surface.


Related Questions

A river flows with a uniform velocity vr. A person in a motorboat travels 1.22 km upstream, at which time she passes a log floating by. Always with the same engine throttle setting, the boater continues to travel upstream for another 1.45 km, which takes her 69.1 min. She then turns the boat around and returns downstream to her starting point, which she reaches at the same time as the same log does. How much time does the boater spend traveling back downstream

Answers

Answer:

 t ’= [tex]\frac{1450}{0.6499 + 2 v_r}[/tex],  v_r = 1 m/s       t ’= 547.19 s

Explanation:

This is a relative velocity exercise in a dimesion, since the river and the boat are going in the same direction.

By the time the boat goes up the river

        v_b - v_r = d / t

By the time the boat goes down the river

        v_b + v_r = d '/ t'

let's subtract the equations

       2 v_r = d ’/ t’ - d / t

       d ’/ t’ = 2v_r + d / t

       [tex]t' = \frac{d'}{ \frac{d}{t}+ 2 v_r }[/tex]

In the exercise they tell us

         d = 1.22 +1.45 = 2.67 km= 2.67 10³ m

         d ’= 1.45 km= 1.45 1.³ m

at time t = 69.1 min (60 s / 1min) = 4146 s

the speed of river is v_r

      t ’= [tex]\frac{1.45 \ 10^3}{ \frac{ 2670}{4146} \ + 2 \ v_r}[/tex]

      t ’= [tex]\frac{1450}{0.6499 + 2 v_r}[/tex]

In order to complete the calculation, we must assume a river speed

          v_r = 1 m / s

       

let's calculate

      t ’= [tex]\frac{ 1450}{ 0.6499 + 2 \ 1}[/tex]

      t ’= 547.19 s

The "problem of perception" is best characterized as?

Answers

Answer:

making sense of a 3-d world from 2-d data

Explanation:

Jshshshsshhsbxbxbxbxbdbdbd

Elizabeth has always believed that people's thoughts can help heal them. She wants to help people use positive thinking to positively affect their
illnesses. What type of psychology would be MOST appropriate for Elizabeth to study?

Answers

Answer: Family

Explanation:

calculate the peak voltage of a mains supply of 240Vrms.​

Answers

Answer:

So 240V RMS is equivalent to 339 V peak, or 679 V peak to peak and can be written as 240 Vrms. (the formula is Vrms = Vmax / √2). The waveform is a sinusoid varying about a neutral, which can also be drawn as a vector with a single arrow pointing away from neutral.

The degree of relationship between two or more variables is _________.

Answers

Two or more variables considered to be related, in a statistical context, if their values change so that as the value of one variable increases or decreases so does the value of the other variable (although it may be in the opposite direction).
And the degree to which two variables vary together determines whether the relationship is strong or weak

How is light energy different from both sound and heat energy?
A.
Sound energy is a wave.
B.
Light energy can exist independently of matter.
C.
Heat energy can radiate from an object.
D.
Light is more energetic when its frequency is higher.

Answers

Answer:

B. Light energy can exist independently of matter.

Explanation:

In science, matter can be defined as anything that has mass and occupies space. Any physical object that is found on earth is typically composed of matter. Matter are known to be made up of atoms and as a result has the property of existing in states.

Generally, matter exists in three (3) distinct or classical phases and these are;

I. Solid.

II. Liquid.

III. Gas.

Light energy is different from both sound and heat energy because light energy can exist independently of matter.

Generally, we know that light energy is a type of electromagnetic waves and as such do not require a medium of propagation for it to travel through a vacuum of space where no particles exist. For example, light energy from distant galaxy of stars and the sun.

However, both sound and heat energy are mechanical waves which are highly dependent on matter for their propagation and transmission.

Points A, B, and C lie along a line from left to right, respectively. Point B is at a lower electric potential than point A. Point C is at a lower electric potential than point B. What would best describes the subsequent motion, if any, of a positively-charged particle released from rest at point B?

Answers

Answer:

Please see below as the answer is self-explanatory.

Explanation:

If the potential at B is lower than A, and the potential at C is lower than B, this means that there is an electric field, directed from A to C.If a positively-charged particle is released at rest at point B, it will be accelerated by the electric field  (which is a force per unit charge, so it produces an acceleration) in the same direction than the field (because it is a positive charge) towards point C.

Marquette King, formerly of the Denver Broncos, is practicingkicking off using a kicking holder with the ball on the ground.For one of the kicks the ball reaches a height of 90.6 m andlands on the ground 53 yds (48.5 m) away. Find the magnitudeof the initial velocity given by his kick to the ball. Treat airresistance as negligible. Hint: Even though the horizontal andvertical motions are independent, there is a quantity that iscommon to both of them.

Answers

Answer:

Explanation:

Maximum height reached = 90.6 m . Range = 48.5 m

. Let u be the initial velocity at angle α .

Horizontal range is covered by horizontal component of u .

Vertical height is achieved by vertical component

v² = u² sin² α - 2gh , t is time taken to attain maximum height .

0 = u² sin² α - 2 x 90.6 x 9.8  

u² sin² α = 2 x 887.88  -------( 1 )

Range R = u² sin2α / g

48.5 = 2 u² sinα . cos α / 9.8

u² sinα . cos α = 237.65 -----------------------------  ( 2 )

( 1 ) / ( 2 )

Tan α = 2 x 887.88 / 237.65 = 7.47

α = 82⁰

u² sin² α = 2 x 887.88

u² sin² 82 = 2 x 887.88

u² = 1812

u = 42.56  m /s

Through what potential difference should electrons be accelerated so that their speed is 1.0 % of the speed of light when they hit the target

Answers

Answer:

Explanation:

Considering non - relativistic approach : ----

Speed of electron = 1 % of speed of light

= .01 x 3 x 10⁸ m /s

= 3 x 10⁶ m /s

Kinetic energy of electron = 1/2 m v²

= .5 x 9.1 x 10⁻³¹ x ( 3 x 10⁶ )²

= 40.95 x 10⁻¹⁹ J

Kinetic energy in electron comes from lose of electrical energy equal to

Ve where V is potential difference under which electron is accelerated and e is electronic charge .

V x e = kinetic energy of electron

V x 1.6 x 10⁻¹⁹ = 40.95 x 10⁻¹⁹

V = 25.6 Volt .

You drive on Interstate 10 from San Antonio to Houston, half the time at 75 km/h and the other half at 106 km/h. On the way back you travel half the distance at 75 km/h and the other half at 106 km/h. What is your average speed (a) from San Antonio to Houston, (b) from Houston back to San Antonio, and (c) for the entire trip

Answers

Answer:

Explanation:

a ) from San Antonio to Houston let distance be d km .

Average speed = total distance / total time

time = distance / speed

Total time = (d / 2 x 75 ) +( d / 2 x 106 )

= .0067 d + .0047 d

= .0114 d

Average speed  = d / .0114 d = 87.72 km /h

b ) from Houston back to San Antonio

Total time = (d / 2 x 106 ) +( d / 2 x 75 )

= .0047 d + .0067 d

= .0114 d

Average speed  = d / .0114 d = 87.72 km /h

c )

For entire trip :

total distance = 2d

total time = 2 x .0114 d

Average speed  = 2 d / 2 x .0114 d

= 87.72 km /h .

define stress engineering science​

Answers

Answer:

Stress, in physical sciences and engineering, force per unit area within materials that arises from externally applied forces, uneven heating, or permanent deformation and that permits an accurate description and prediction of elastic, plastic, and fluid behaviour.

I hope it's helpful!

One reason why it’s often easy to miss an action-reaction pair is because of the ________ of one of the objects.

Answers

Answer:

an action-reaction pair is because one of the objects is often much more massive and appears to remain motionless when a force acts on it. It has so much inertia, or tendency to remain at rest, that it hardly

Fred's lightbulb is 45% efficient, and Fran's is 75% efficient. If they both use the same amount of electric energy, which produces more light energy? ​

Answers

Answer:

Frank's 75% efficient light bulb will shine brighter.

Explanation:

The brightness of a bulb is gotten from the power equation;

P = I²R

The more the power rating in watts, the more the brightness.

Now, if they both use the same amount of energy but yet have different efficiency, it means we will just multiply the efficiency by the power.

Thus, 75% efficiency will yield more power than a 45% efficient one.

Therefore, Frank's light bulb will shine brighter.

Connective Tissue in a tendon is

Answers


Overview. A tendon is a fibrous connective tissue which attaches muscle to bone. Tendons may also attach muscles to structures such as the eyeball. A tendon serves to move the bone or structure.

An ideal monatomic gas initially has a temperature of 300 K and a pressure of 5.79 atm. It is to expand from volume 420 cm3 to volume 1450 cm3. If the expansion is isothermal, what are (a) the final pressure and (b) the work done by the gas

Answers

Answer:

a) The final pressure is 1.68 atm.

b) The work done by the gas is 305.3 J.

Explanation:

a) The final pressure of an isothermal expansion is given by:

[tex] T = \frac{PV}{nR} [/tex]

[tex] T_{i} = T_{f} [/tex]

[tex] \frac{P_{i}V_{i}}{nR} = \frac{P_{f}V_{f}}{nR} [/tex]

Where:

[tex]P_{i}[/tex]: is the initial pressure = 5.79 atm

[tex]P_{f}[/tex]: is the final pressure =?

[tex]V_{i}[/tex]: is the initial volume = 420 cm³

[tex]V_{f}[/tex]: is the final volume = 1450 cm³

n: is the number of moles of the gas

R: is the gas constant

[tex] P_{f} = \frac{P_{i}V_{i}}{V_{f}} = \frac{5.79 atm*420 cm^{3}}{1450 cm^{3}} = 1.68 atm [/tex]

Hence, the final pressure is 1.68 atm.

b) The work done by the isothermal expansion is:

[tex] W = P_{i}V_{i}ln(\frac{V_{f}}{V_{i}}) = 5.79 atm*\frac{101325 Pa}{1 atm}*420 cm^{3}*\frac{1 m^{3}}{(100 cm)^{3}}ln(\frac{1450 cm^{3}}{420 cm^{3}}) = 305.3 J [/tex]

Therefore, the work done by the gas is 305.3 J.

I hope it helps you!        

Carousel conveyors are used for storage and order picking for small parts. The conveyorsrotate clockwise or counterclockwise, as necessary, to position storage bins at the storageand retrieval point. The conveyors are closely spaced, such that the operators travel timebetween conveyors is negligible. The conveyor rotation time for each item equals 1 minute;the time required for the operator to retrieve an item after the conveyor stops rotatingequals 0.25 minute. How many carousel conveyors can one operator tend without creatingidle time on the part of the conveyors

Answers

Answer:

the number of carousel conveyors that an operator can operate without any idle time is 5

Explanation:

Given the data in the question;

first we express the equation for number of carousel conveyors that can be operated by an operator;

n' = [tex]\frac{(a + t)}{( a + b)}[/tex]

where a is the concurrent activity time ( 0.25 minute )

b is the independent operator activity time

t is the independent machine activity time( 1 )

Now independent activity time is zero as the operator is not performing any inspection or packaging tasks.

So time taken for the operator to retrieve the finished item at the end of the process is the concurrent activity and independent machine activity time, the conveyor rotation time of each item

so

we substitute

0.25min for a, 1 for t and 0min for b

n' = [tex]\frac{(0.25min + 1min)}{( 0.25min+ 0 min)}[/tex]

n' = 1.25 min / 0.25

n' - 5

Therefore, the number of carousel conveyors that an operator can operate without any idle time is 5

The surface area of a postage

stamp is 0.00600 m^2, and the air

exerts 1.00 atm of pressure on it.

How much force does it exert on

the stamp?

(Hint: The standard unit for

pressure is Pa.)

(Unit = N)

Answers

Answer:

Force = 607.95 Newton

Explanation:

Given the following data;

Area = 0.00600 m^2

Pressure = 1 atm to Pascal = 101325 Pa

To find the force;

Pressure = Force/area

Force = pressure * area

Substituting into the equation, we have;

Force = 101325 * 0.00600

Force = 607.95 Newton.

Therefore, the amount of force exerted by the air on the stamp is 607.95 Newton.

What is the mass of an object if it is moving at a speed of 10 m/s and has 400 J of kinetic energy?

Answers

Answers:

8 kg

Explanation:

Kinetic Energy = (mass × velocity × velocity) ÷ 2

We know that Kinetic Energy = 400 J and velocity = 10 m/s.

KE = (m × v × v) ÷ 2

400 J = (m × 10 m/s × 10 m/s) ÷ 2

400 J = m × 50 m^2/s^2

To find the mass you will divide 400 J and 50 m^2/s^2.

m = 8 kg

You can also check it if it gives you 400 J.

KE = (m × v × v) ÷ 2

KE = (8 kg × 10 m/s × 10 m/s) ÷ 2

KE = 400 J

So this means that the mass is 8 kg. I know that it is a bit confusing, but when you do J (joules) ÷ m^2/s^2 = kg (kilograms). Hope this helps, thank you !!

A plastic rod 1.6 m long is rubbed all over with wool, and acquires a charge of -9e-08 coulombs. We choose the center of the rod to be the origin of our coordinate system, with the x-axis extending to the right, the y-axis extending up, and the z-axis out of the page. In order to calculate the electric field at location A = < 0.7, 0, 0 > m, we divide the rod into 8 pieces, and approximate each piece as a point charge located at the center of the piece.

Answers

Solution :

Length of the plastic rod , L = 1.6 m

Total charge on the plastic rod , Q = [tex]$-9 \times 10^{-8}$[/tex] C

The rod is divided into 8 pieces.

a). The length of the 8 pieces is , [tex]$l=\frac{L}{8}$[/tex]

                                                         [tex]$=\frac{1.6}{8}$[/tex]

                                                         = 0.2 m

b). Location of the center of the piece number 5 is given as : 0 m, -0.09375 m, 0 m.

c). The charge q on the piece number 5 is given as

[tex]$q=\frac{Q}{L}\times l$[/tex]

[tex]$q=\frac{-9 \times 10^{-8}}{1.6}\times0.2$[/tex]

 = [tex]$-1.125 \times 10^{-8}$[/tex] C

d). WE approximate that piece 5 as a point charge and we need to find out the field at point A(0.7 m, 0, 0) only due to the charge.

We know,  the Coulombs force constant, k = [tex]$8.99 \times 10^9 \ N.m^2/C^2$[/tex]

So the X component of the electric field at the point A  is given as

[tex]$E_x = 8.99 \times 10^9 \times 1 \times 10^{-8} \ \cos \frac{187.628}{0.70625}$[/tex]

     = -126.15 N/C

The Y component of the electric field at the point A is

[tex]$E_y = 8.99 \times 10^9 \times 1 \times 10^{-8} \ \sin \frac{187.628}{0.70625}$[/tex]

    = -16.93 N/C

Now since the rod and the point A is in the x - y plane, the z component of the field at point A due to the piece 5 will be zero.

∴ [tex]$E_z=0$[/tex]

Thus, [tex]$E= <-126.15,-16.93,0>$[/tex]

Which of the following best describes what were wrong with the scientists study

Answers

where is the scientists study?

Choose the best explanation from among the following:_________.
1. Charge is conserved, and therefore the mass of the object will remain the same.
2. A positive charge increases an object's mass; a negative charge decreases its mass.
3. To give the object a negative charge we must give it more electrons, and this will increase its mass.

Answers

Answer: 3. To give the object a negative charge we must give it more electrons, and this will increase its mass.

Explanation:

Suppose we have an object and we negatively charge it.

Then we are "adding" N electrons to the object.

Remember that the mass of an electron is:

m = 9.11*10^(-31) kg

Then if we add N electrons to an object of mass M, the new mass of the object will be:

Mass = M + N*9.11*10^(-31) kg

So we will have an (almost negligible) increase of the mass of the object.

(Something similar can happen if the object is positively charged, where we remove electrons, then the mass of the object decreases)

Then the correct option is:

3. To give the object a negative charge we must give it more electrons, and this will increase its mass.

A car traveling 85 km/h is 250 m behind a truck
traveling 73 km/h.

Answers

Time needed = t = 20.83 s

Further explanation

Given

car speed = 85 km/h

truck speed = 73 km/h

Required

the time it takes for the car to reach the truck

Solution

When the car reaches the truck, the distance between them will be the same

x car - 250 m = x truck

General formula for distance (d) :

d = v.t

So the equation becomes :

85t-250 = 73t

12t=250

t = 20.83 s

Using your knowledge on personal care products, how does sunscreen

lotion protect your skin from the damaging effect of ultraviolet rays?

Explain why of x-rays and gamma rays are commonly used in

radiotherapy.​

Answers

Answer:

Ultraviolet rays from sun are very harmful from skin and can cause sunburn and skin diseases especially ultraviolet B rays. A sunscreen  lotion act as a protection barrier on the skin that restrict the direct contact of UV rays with skin and filter the harmful rays to enter the skin.

Radiotherapy is a medical therapy use to treat cancer. Radiotherapy commonly uses x-rays and gamma rays because they are high-energy particles or waves that kills or destroys the cancer cells.

Sunscreen lotion is able to filter this damaging ultraviolet radiation and prevent it from damaging the skin.

The sun reaches us from outer space brings ultraviolet rays to us. Ultraviolet rays are known to have some damaging effects on the skin. One way to protect our skin from this damaging ultraviolet rays is to use sunscreen lotion which is able to filter this damaging ultraviolet radiation and prevent it from damaging the skin.

X-rays and gamma rays are used in radiotherapy because they are light energy rays which are able to penetrate and destroy malignant cells in the body.

Learn more: https://brainly.com/question/13695751

A simple pendulum of length 5.5 m makes 10.0 complete swings in 25 s what is the acceleration due to gravity at the location of the pendulum ?

Answers

Answer:

The acceleration due to gravity at the location of the pendulum is 34.74 m/s².

Explanation:

Given that,

The length of a simple pendulum, l = 5.5 m

It makes 10.0 complete swings in 25 s.

Frequency of pendulum,

[tex]f=\dfrac{10}{25}\\\\f=0.4\ Hz[/tex]

The time period of a simple pendulum is given by :

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

Frequency,

[tex]f=\dfrac{1}{T}\\\\f=\dfrac{1}{2\pi \sqrt{\dfrac{l}{g}} }\\\\f=\dfrac{1}{2\pi}\sqrt{\dfrac{g}{l}}[/tex]

g is the acceleration due to gravity at the location where the pendulum is placed. So,

[tex]f^2=\dfrac{g}{4\pi^2l}\\\\g=f^2\times 4\pi^2l\\\\g=0.4^2\times 4\pi^2\times 5.5\\\\g=34.74\ m/s^2[/tex]

So, the acceleration due to gravity at the location of the pendulum is 34.74 m/s².

A mass of 10. kg is placed on the end of a 0.50-meter pendulum. What is the period of the pendulum?

Answers

Answer:

T = 1.41 seconds

Explanation:

Given that,

The mass placed in the pendulum, m = 10 kg

The length of the pendulum, l = 0.5 m

We need to find the period of the pendulum. The relation for the period of the pendulum is given by :

[tex]T=2\pi \sqrt{\dfrac{l}{g}} \\\\T=2\pi \sqrt{\dfrac{0.5}{9.8}} \\\\T=1.41\ s[/tex]

So, the time period of the pendulum is 1.41 seconds.

For anyone that needs the correct answer without POS trolls:

The answer is 1.4 s

Thank me later :)

A baseball player hits a 0.15 kg 0.15kg0, point, 15, start text, k, g, end text baseball that is initially at rest, changing its momentum by 11 kg ⋅ m s 11 s kg⋅m ​ 11, start fraction, start text, k, g, end text, dot, start text, m, end text, divided by, start text, s, end text, end fraction.

Answers

Answer:

73.3m/s

Explanation:

We can find the velocity of the player.

Momentum = mass * velocity

Given

Mass = 0.15kg

Momentum = 11kgm/s

Get the velocity

Velocity = Momentum/Mass

Velocity = 11/0.15

Velocity = 73.3m/s

Hence the velocity of the player is 73.3m/s

Can someone help me answer please

Answers

Answer:

4=Conduction by convection by radiation.

Explanation:

Hope it will help you! It may be short but I don't know how to write it in blank aafai milayera lekha Hai blanks ma

First you lift an object from the floor onto a shelf. Then you move the object back to the floor. do you perform the same amount of work each time? Explain.

Answers

Not really, let’s say a gallon of milk, that’s heavy, so it would be harder to lift it than to put it down. Right? Hope this helps :>

In a game of ice hockey, you use a hockey stick to hit a puck of mass 0.16 kg that slides on essentially frictionless ice. During the hit you exert a constant horizontal force on the puck that gives it an acceleration of 75 m/s2 for a fraction of a second. During the hit, what is the magnitude of the horizontal force that you exert on the puck

Answers

Answer:

12N

Explanation:

given- mass, acelation

Fnet=ma= .16kg*75m/s2

Fnet=12 N only force no friction given.

According to Coulomb's Law, if the distance between two charged particles is doubled, the electric force will be _________. *

Answers

Answer: reduced by 1/4

Explanation:

The force will be reduced by 1/4. Try plugging in 2r, then squaring it. You will get 4r^2, which is essentially dividing the force by 4

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