in a collision, a 25.0kg mass moving at 3.0m/s transfers all of its momentum to a 5.0kg mass. What is the velocity of the 5.0kg mass after the collision?

Answers

Answer 1

Answer:

Explanation:

The 25.0 kg mass has momentum before the collision of

p = 25.0(3.0) = 75 kg•m/s

If all this momentum gets transferred into a 5.0 kg mass, the velocity of the 25.0 kg mass will be zero and the velocity of the 5.0 kg mass will be

75 / 5.0 = 15.0 m/s

Getting this to occur will require an addition of a significant amount of energy via an internal explosion or release of spring potential energy. This can be shown by looking at kinetic energies.  

Initial system kinetic energy is ½(25.0)3.0² = 112.5 Joules

After the collision, system kinetic energy is ½(5.0)25² = 1,562.5 Joules

so 1562.5 - 112.5 = 1450 Joules of energy must be released during the collision to complete this scenario.

The most efficient energy transfer without energy release is an ideal elastic collision. Had these two masses been in such a collision with the given initial conditions, the 5 kg mass would have moved away at 5.0 m/s taking with it 5(5) = 25 kg•m/s of momentum leaving the 25 kg mass with 75 - 25 = 50 kg•m/s of momentum and a velocity of 50/25 = 2.0 m/s. Both masses are now traveling in the same direction as the original velocity, but at different speeds. Notice kinetic energy is conserved in elastic collisions

½(25)2² + ½(5.0)5² = 112.5 Joules.

The only time one mass can transfer its entire momentum to another mass without additional energy addition or subtraction is when the two colliding masses are identical in magnitude. Think pool balls colliding on a table.


Related Questions

2. a) A disc rotates about its axis at speed 25 revolutions per minute and takes 15 s to stop. Calculate the
i) angular acceleration of the disc.
ii) number of rotation of the dise makes before it stops. ​

Answers

The statement shows a case of rotational motion, in which the disc decelerates at constant rate.

i) The angular acceleration of the disc ([tex]\alpha[/tex]), in revolutions per square second, is found by the following kinematic formula:

[tex]\alpha = \frac{\omega_{f}-\omega_{o}}{t}[/tex] (1)

Where:

[tex]\omega_{o}[/tex] - Initial angular speed, in revolutions per second.[tex]\omega_{f}[/tex] - Final angular speed, in revolutions per second. [tex]t[/tex] - Time, in seconds.

If we know that [tex]\omega_{o} = \frac{5}{12}\,\frac{rev}{s}[/tex], [tex]\omega_{f} = 0\,\frac{rev}{s}[/tex] y [tex]t = 15\,s[/tex], then the angular acceleration of the disc is:

[tex]\alpha = \frac{0\,\frac{rev}{s}-\frac{5}{12}\,\frac{rev}{s}}{15\,s}[/tex]

[tex]\alpha = -\frac{1}{36}\,\frac{rev}{s^{2}}[/tex]

The angular acceleration of the disc is [tex]\frac{1}{36}[/tex] radians per square second.

ii) The number of rotations that the disk makes before it stops ([tex]\Delta \theta[/tex]), in revolutions, is determined by the following formula:

[tex]\Delta \theta = \frac{\omega_{f}^{2}-\omega_{o}^{2}}{2\cdot \alpha}[/tex] (2)

If we know that [tex]\omega_{o} = \frac{5}{12}\,\frac{rev}{s}[/tex], [tex]\omega_{f} = 0\,\frac{rev}{s}[/tex] y [tex]\alpha = -\frac{1}{36}\,\frac{rev}{s^{2}}[/tex], then the number of rotations done by the disc is:

[tex]\Delta \theta = 3.125\,rev[/tex]

The disc makes 3.125 revolutions before it stops.

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Need help on this thank you

Answers

Answer:

TRUE - In any collision between two objects, the colliding objects exert equal and opposite force upon each other. This is simply Newton's law of action-reaction.

Which statement describes friction?

Answers

Answer:

include the statements pls so i can choose wich one it is and tell you

Explanation:

A mover pushes a 45 kg crate across a level floor with a force of 300 N, but the crate accelerates at a rate of only 4.44 m/s2 because a friction force opposes the crate's motion. What is the magnitude of this force of friction? 300 N Force of Friction O A. 50 N N OB. 25 N C. 15 N 0 D. 100 N​

Answers

By Newton's second law, the net force on the crate is

F = 300 N - f = (45 kg) (4.44 m/s²)

where f is the magnitude of friction. Solve for f :

300 N - f = (45 kg) (4.44 m/s²)

f = 300 N - (45 kg) (4.44 m/s²)

f = 100.2 N ≈ 100 N (D)

A spring of spring constant k = 200 N m−1 is slowly extended from an extension of 3.0 cm to an extension of 5.0 cm. Calculate the work done by the extending force. 60

Answers

Answer:

31

Explanation:

No need

The correct answer is 31 I did it

4. What is the density of a block with a mass of 36 g and a volume of 9 cm?
O A 45 g/cm3
O B.27 g/cm
O 0.4 g/cm
O D. 0.25 g/cm

Answers

Answer:

0.4 g/cm

Explanation:

density (g cm ³) = mass (g)

÷

volume (cm³)

Answer:

C. 4 g/cm

Explanation:

Use the formula:

density = mass ÷ volume

mass = 36volume = 9

Sub in the values:

density = 36 ÷ 9 = 4 g/cm

Answer = 4 g/cm

A bowling ball, basketball, and tennis ball are all raised to the same height above the ground. Give the order of objects from the least potential energy to the most

Answers

Answer:

bowling ball, basket ball, tennis ball

Explanation:

Is my answer correct

Answers

Answer:

it right congratulations

Answer:

A

Explanation:

Simply option A is correct

It's a bit of a common sense question

At the highest point it's velocity will be automatically 0 since it is in rest and so is the acceleration

define potential difference as used in electricity​

Answers

Potential difference is the difference in the amount of energy that charge carriers have between two points in a circuit.

Potential difference is the difference in the amount of energy that charge carriers have between two points in a circuit. ... The energy is transferred to the electrical components in a circuit when the charge carriers pass through them. We use a voltmeter to measure potential difference (or voltage).

Which statement correctly describes the relationship between thermal energy and particle movement?(1 point)

As thermal energy increases, there is more particle movement.
As thermal energy increases, there is more particle movement.

As thermal energy increases, there is less particle movement.
As thermal energy increases, there is less particle movement.

As thermal energy increases, particle movement does not change.
As thermal energy increases, particle movement does not change.

As thermal energy increases, it is not possible to predict particle movement.
As thermal energy increases, it is not possible to predict particle movement.

Answers

Answer:

As thermal energy increases,there is more particle movement

what is an electrostatic phenomenon?​

Answers

Answer:

Electrostatic phenomenon is a from the forces that electric charges exert on each other.

A 220g mass is on a frictionless horizontal surface at the end of a spring that has a force constant of 7.0N/m The mass is displaced 5 2m from its equilibrium position and then released to undergo simple harmonic motion.
At what displacement from the equilibrium position is the potential energy equal to kinetic energy?​

Answers

Answer:

Explanation:

Your numbers seem wonky, so I'll just assume that the initial displacement is a distance A (Amplitude) from the equilibrium position. Spring constant = k

Initial potential energy is

PE = ½kA²

As potential energy and kinetic energy are constantly exchanging in SHM,

the position x where half of the original spring potential exists is found where

½kx² = ½(½kA²)

    x² = ½A²

    x = (√0.5)A

    x ≈ 0.707A

just plug in your actual starting position A

With A = 5.2 cm

x = 3.67695... 3.7 cm

A machine whose efficiency is 75% is used to lift a load of 100m.calculate the effort put into the machine if it has a velocity ratio of 4.

Answers

Explanation:

M.A = load / Effort

efficiency = M.A/V.R X 100

75 = M.A / 4 X 100

75 = 25 X M.A

M.A = 75/25 = 3

M.A = load / effort

3 = 100/E

E = 100/3 = 33.333

A machine whose efficiency is 75% is used to lift a load of 100m. the effort needed to put into the machine is 33.33 meters if the velocity ratio is 4.

What is the mechanical advantage?

Mechanical advantage is defined as a measure of the ratio of output force to input force in a system, It is used to analyze the forces in simple machines like levers and pulleys.

Mechanical advantage = output force(load) /input force (effort)

Simple machines like static pulleys, as well as a movable pulleys, provide a great amount of mechanical advantage.

A machine whose efficiency is 75% is used to lift a load of 100m.calc if it has a velocity ratio of 4.

As we know that the mechanical advantage of a machine is equal to the product of its efficiency and velocity ratio.

mechanical advantage  = velocity ratio   ×Efficiency

       =4 × 0.75

       = 3

The mechanical advantage is 3 , which means the ratio of load to effort is 3

load / effort = 3

100 m/effort =3

effort = 33.33 m

Thus, the effort put into the machine comes out to be 33.33 m.

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Find the speed required to throw a ball straight up and it return 6 seconds later. Neglect air resistance

Answers

Answer:

the ball will go up 3s and down 3s

v=gt

where t=3s and g=9.8m/s^2

distance=v0(t)+(1/2)gt^2

where initial velocity (v0)=0

Explanation:

The speed required to throw a ball straight up and returns 6 seconds later would be 29.43 meters/seconds.

What are the three equations of motion?

There are three equations of motion given by Newton,

v = u + at

S = ut + 1/2×a×t²

v² - u² = 2×a×s

As given in the problem we have to find the speed required to throw a ball straight up and it returns 6 seconds later,

S = ut + 1/2*a*t²

0 = u×6 + 0.5×(-9.81)×6²

0 = 6u - 176.8

6u = 176.8

u = 176.8/6

u = 29.43 meters / seconds

Thus, the speed required to throw a ball straight up and returns 6 seconds later would be 29.43 meters/seconds.

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A 23 g bullet traveling at 230 m/s penetrates a 2.0 kg block of wood and emerges cleanly at 170 m/s. If the block is stationary on a surface with a coefficient of kinetic friction of 0.15 when hit, how far does it move after the bullet emerges?

Answers

The distance traveled by the wood after the bullet emerges is 0.16 m.

The given parameters;

mass of the bullet, m = 23 g = 0.023 gspeed of the bullet, u = 230 m/smass of the wood, m = 2 kgfinal speed of the bullet, v = 170 m/scoefficient of friction, μ = 0.15

The final velocity of the wood after the bullet hits is calculated as follows;

[tex]m_1u_1 + m_2 u_2 = m_1v_1 + m_2v_2\\\\0.023(230) + 2(0) = 0.023(170) + 2v_2\\\\5.29 = 3.91 + 2v_2\\\\2v_2 = 1.38\\\\v_2 = \frac{1.38}{2} = 0.69 \ m/s[/tex]

The acceleration of the wood is calculated as follows;

[tex]\mu = \frac{a}{g} \\\\a = \mu g\\\\a = 0.15 \times 9.8\\\\a = 1.47 \ m/s^2[/tex]

The distance traveled by the wood after the bullet emerges is calculated as follows;

[tex]v^2 = v_0^2 + 2as\\\\v^2 = 0 + 2as\\\\v^2 = 2as\\\\s = \frac{v^2}{2a} \\\\s = \frac{(0.69)^2}{2(1.47)} \\\\s = 0.16 \ m[/tex]

Thus, the distance traveled by the wood after the bullet emerges is 0.16 m.

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Which of the following happens when a substance melts?

Answers

Answer:

hola como estas hablas español

Explanation:

What is the mass of an object that is experiencing a net force of 225 N and an acceleration of 3.0 m/s^2?​

Answers

Answer:

Mass of a object 75 Kilograms

Explanation:

Net force acting on an object, [tex]Fnet = 225N[/tex]

Acceleration produced, [tex]a = 3.0m/s^2[/tex]

According to Newton's second law :

F = m a

[tex]M =\frac{F}{a}[/tex]

[tex]m =\frac{225N}{300m/s^2}[/tex]

[tex]m= 75 Kg[/tex]

So, the mass of an object is 75kg.

Hence, this is the required solution.

Answer:

75 kg.

Explanation:

Net Force

[tex]\sf \longmapsto F_{net} = 225N[/tex]

Acceleration produced

[tex]\sf \longmapsto \: a = 3 .0 m / {s}^{2}[/tex]

According to Newton's 2nd Law –

F = m•a

[tex]\sf \longmapsto \: M = \frac{F}{A} [/tex]

[tex]\sf \longmapsto \: M = \frac{225N}{300m/s ^{2} } [/tex]

[tex]\sf \longmapsto \: M = \: 75 \: kg[/tex]

Therefore, the mass of an object is 75 kg.

how can I become a good science student ?​

Answers

Answer:

Study hard , focus on your studies and alyways ask questions .

Study, revise, write notes, listen in class, don't let yourself be distracted by others, and do the work in class...maybe join stem or science club if you wanna

Hope this helped you- have a good day bro cya)

what is the minimum mass in Mol. of plutonium 234 needed to reach a critical mass nuclear reaction?​

Answers

Answer:

vddvdvvdvffdfvd

Explanation:

A double concave lens is a ________ lens, and a double convex lens is a ______ lens.
a.
converging, diverging
c.
converging, converging
b.
diverging, converging
d.
diverging, diverging

Answers

Answer:

b. diverging, converging

Answer:diverging, converging

Explanation:

QUESTION 5 When 235U is bombarded with one neutron, fission occurs and the products are three neutrons, 94Kr and?

a. 139Ba
b. 141Ba
c. 139Ce
d. 139Xe​

Answers

The answer is of the question is A

HELPPPP

The maximum force of sliding friction between a 10 kg rubber box and the concrete
floor is 64 N. How much force should a worker push on the box with if he wants it to
move at a constant velocity?
1) A little less than 64 N
2)A little more than 64 N
3)Exactly 64 N.
4)Exactly 640 N

Answers

The force that will move the box at constant velocity must be a little more than 64 N.

The coefficient of sliding friction is obtained from the formula;

μ= F/R

Where;

F = frictional force

μ = coefficient of sliding friction

R = Normal reaction

It is necessary to note that the force that will move the body must be greater than the frictional force acting between the body and the surface in order to move the body. Hence, the force that will move the box at constant velocity must be a little more than 64 N.

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Please help with this question, it’s for physical science

Answers

Answer:

s times t

Explanation:

The equation for distance is D = st

Answer:

D is the correct answer (D=S*T)

This is an algebraic law; if you are to move the denominator or numerator to the other side of the equation, you must multiply it by the other side.

S=D/T is the same as D=S*T.

so distance=speed times time.

so if you are going 50 miles per hour, you multiply that times time, say one hour. you get your D distance which is 50 miles.

in a closed system of a cannon and cannonball, which changes would both results in an increase in the kinetic energy of the cannonball when fired from the cannon?

A) decrease the mass of the cannon or decrease the mass of the cannonball

B) increase the mass of the cannon or decrease the mass of the cannonball

C) decrease the mass of the cannon or increase the mass of the cannonball

D) increase the mass of the cannon or increase the mass of the cannonball

Answers

the answer is b because when it increases the mass decreases the cannon ball

Changes that would results in an increase in the kinetic energy of the cannonball in a closed system, when it is fired from the cannon is B:increase the mass of the cannon or decrease the mass of the cannonball.

A closed system can be considered one that is not been affected by external forces. With the conservation of momentum, there would be collisions as well inexplosions.

This explains that when a cannon is fired, there would be gain of forward momentum by the cannon ball, while the cannon experience backward momentum.

For the kinetic energy of the cannonball to increase, when fired from the cannon, then the mass is the cannon would be increased or the mass of the cannonball would be decreased.

Therefore, option B is correct.

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A flea can jump with an initial velocity of 2.2 m/s at an angle of 21° with respect to the
horizontal.

Answers

Answer:

Explanation:

If no one can see it because the lights were out. Did the flea really jump?

What do you want here?

Max height (2.2sin21)²/ 2(9.8) = 3.2 cm

Time of flight 2(2.2sin21)/ (9.8) = 0.16 s

distance of flight (2.2cos21)(0.16) = 33 cm

A ball moving 2 ft/s rolls off a table (on earth) that is 32 inches high. How long will it take the ball to hit the floor answer

Answers

Answer:When the ball rolls off the edge of the table, it will continue moving forward at 2.0 m/s until it hits the floor.

Explanation:This is what I would say is the answer bc I had to do reasearch on a lot of this for my work this year so if its not im veery sorry

True or False

In newton's 2nd law, f=ma there is a correlation between the force and acceleration. This supports that there is a causal relationship that acceleration has on the net force.

Answers

Answer: See explanation

Explanation:

Please see attached picture. Due to the fact one of the words in the equation F=ma contains a word not allowed.

Two students were pushing a heavy sofa. One student pushed with a force of 200.0 N to the right, while the other pushed with a force of 150.0 N to the right. The floor exerted a frictional force of 100.0 N. If the sofa's mass is 91.0 kg, what is its acceleration? Round your answer to three significant figures.

Answers

Answer:

Explanation:

F = ma

a = F/m

a = (200.0 + 150.0 - 100.0) / 91.0

a = 250.0/91.0

a = 2.7472527...

a = 2.75 m/s²

A diffraction grating, ruled with 300 lines per mm, is illuminated with a white light source at normal incidence.
(i) What is the angular separation, in the third-order spectrum, between the 400 nm and 600 nm lines? [5]
(ii) Water (of refractive index 1.33) now fills the whole space between the grating and the screen. What is the angular separation, in the first-order spectrum, between the 400 nm and 600 nm lines? [5]​

Answers

the expression for diffraction grating allows to find the results for the questions for the angular separation are:

i) The third order is Δθ = 0.203 rad.

ii) The first order with water is Δθ = 0.046 rad.

The diffraction grating is a system formed by a large number of equally spaced lines whose diffraction is given by the expression.

          d sin θ = m λ

Where d is the distance between two lines, θ is the angle of diffraction, the order of diffraction and λ is the wavelength.

i) Let's start by looking for the separation between two lines

Let's use a rule of direct proportions. If there are 300 lines in 1 mm, what distance is there between two lines.

         d = 1 lines (1 mm / 300 lines) = 3,333 10⁻³ mm

         d = 3.333 10⁻⁶ m

Let's find the angle of diffraction for the third order (m = 3) for each wavelength.

λ₁ = 400 nm = 400 10⁻⁹ m

         sin θ₁ = [tex]\frac{m \ \lambda }{d}[/tex]m λ/ d

         sin θ₁ = [tex]\frac{3 \ 400 \ 10^{-9} }{3.333 \ 10^{-6} }[/tex]  

         θ₁ = sin⁻¹ 0.3600

         θ₁ = 0.368 rad

λ₂ = 600 nm = 600 10⁻⁹ m

         sin θ₂ = [tex]\frac{3 \ 600 \ 10^{-9} }{3.333 \ 10^{-6} }[/tex]  

         θ₂ = sin⁻¹ 0.5401

         θ₂ = 0.571 rad

The angular separation is

         Δθ = θ₂ - θ₁

         Δθ = 0.571 - 0.368

         Δθ = 0.203 rad

ii) In this case, the separation between the network and the observation screen is filled with water.

When the rays leave the network they undergo a refraction process, for which they must comply with the relationship.

           [tex]n_i \ sin \theta_1 = n_r \ sin \theta_r[/tex]

The incident side is in the air, therefore its refractive index is n_i = 1 and when it passes into the water with refractive index n_r = 1.33.

Let's start looking for the incident angles for the first order of diffraction.

      m = 1

λ₁ = 400 nm

         θ₁ = sin⁻¹  [tex]\frac{1 \ 400 \ 10^{-9}}{3.33 \ 10^{-6}}[/tex]

         θ₁ = 0.120 rad

λ₂ = 600 nm

        θ₂ = sin⁻¹¹ [tex]\frac{1 \ 600 \ 10^{-9} }{3.33 \ 10^{-6}}[/tex]

        θ₂ = 0.181 rad

we use the equation of refraction.

         [tex]\theta_r[/tex]  = sin⁻¹ ([tex]\frac{n_i}{n_r} \ sin \ \theta_i[/tex] )

λ₁ = 400 nm  

       θ₁ = sin¹ ([tex]\frac{1 sin 0.120}{1.33}[/tex]

       θ₁ = 0.090 rad

λ₂ = 600 nm

        θ₂ =sin⁻¹  [tex]\frac{1 sin 0.181}{1.33}[/tex]

        θ₂ = 0.1358 rad

The angular separation is

          Δθ = 0.1358 - 0.090

          Δθ = 0.046 rad.

In conclusion using the relation for the diffraction grating we can find the results for the questions about angular separation are:

       i) The third order is Δθ = 0.203 rad.

      ii) The first order with water is Δθ = 0.046 rad.

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A uniform string of length 0.50 m is fixed at both ends. Find the
wavelength of the fundamental mode of vibration. If the wave
speed is 300 mis, find the frequency of the fundamental and next
possible modes.

Answers

Answer:

configuration of string:

Node - Antinode - Node    or N-A-N

This is 1/2 wavelength since a full wavelength is N-A-N-A-N

f (fundamental) = V / wavelength

F0 = 300 m/s / 1 m = 100 / sec

F1 = 300 m/s / .5 m = 600 / sec

Each increase is a multiple of the fundamental since the wavelength

increases by 1/2 wavelength to keep nodes at both ends of the string

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