A 200 g blob of clay moves with a speed of 10 m/s towards a 300 g cart that is initially at rest.

a. What is the momentum of the system before the blob of clay strikes the cart?

b. What must be the momentum of the system after they come together?

c. If the blob of clay sticks to the cart, with what speed will the clay and cart move after they come together?

Answers

Answer 1

Answer:

a. 2 kg*m/s

b. [tex]p_{T_{f}} = 0.5v_{f} = 2 kg*m/s[/tex]

c. 4 m/s

Explanation:

a. The momentum of the system ([tex]p_{Ti}[/tex]) before the blob of clay strikes the cart is:

[tex] p_{Ti} = p_{b} + p_{c} [/tex]

Where:

[tex]p_{b}[/tex] is the momentum of the blob clay

[tex]p_{c}[/tex] is the momentum of the car      

[tex] p_{Ti} = m_{b}v_{b} + m_{c}v_{c} [/tex]

Since the car is initially at rest, [tex]v_{c}[/tex] = 0

[tex] p_{Ti} = 200 g*\frac{1 kg}{1000 g}*10 m/s + 0 = 2 kg*m/s [/tex]

b. The momentum of the system after they come together:

[tex]p_{T_{f}} = m_{b}v_{b} + m_{c}v_{c}[/tex]

Since they come together, [tex]v_{b}[/tex] =

[tex]p_{T_{f}} = v_{f}(m_{b} + m_{c}) = v_{f}(0.2 kg + 0.3 kg) = 0.5v_{f}[/tex]   (1)

Because we do not have the final speed we can not calculate the final momentum.

                   

c. We can find the speed of the clay and car by conservation of the momentum:

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

The initial momentum of the system was founded in part "a" (p = 2 kg*m/s), so we have:

[tex] 2 kg*m/s = m_{b}v_{b_{f}} + m_{c}v_{c_{f}} [/tex]

Again, when they come together, the final speed is the same:

[tex] 2 kg*m/s = v_{f}(m_{b} + m_{c}) [/tex]                

[tex] v_{f} = \frac{2 kg*m/s}{0.2 kg + 0.3 kg} = 4 m/s [/tex]

Now, since we found the final speed we can calculate the momentum of the system after they come together (equation 1):        

[tex] p_{T} = 0.5v_{f} = 0.5 kg*4m/s = 2 kg*m/s [/tex]

I hope it helps you!                  


Related Questions

A water tank is filled with up to 3.5 m height.Calculate the pressure given by the tank at its bottom​

Answers

Answer:

96.04Pa

Explanation:

height=3.5m

gravity=9.8%

density=9.8/3.5

=2.8

Preassure=h×g×d

=3.5×9.8×2.8

=96.04Pa

Water boils at 212°F. Which temperature is an equivalent temperature?

Answers

[tex]\mathrm {Hey, there!}[/tex]

Let's solve your problem:

We will convert your number, 212°F, to Kelvin and Celsius.

212°F is equal to 100° Celsius.

Now, let's do the Kelvin convert.

To convert Celsius to Kelvin, we have to add 273.5 to the amount of Celsius.

100° + 273.5 = 373.5

We have all our conversions. Finally, let's set them out.

Fahrenheit: 212°F

Celsius: 100°C

Kelvin: 373.5°K

it is harmful to settle near the airport why

Answers

Yes, plane accidents can happen near you, it can harm your property and cause a disaster.



005 (part 1 of 2) 10.0 points

A runner is jogging in a straight line at a

steady vr= 8.5 km/hr. When the runner is

L=6.4 km from the finish line, a bird begins

flying straight from the runner to the finish

line at vý= 17 km/hr (2 times as fast as the

runner). When the bird reaches the finish

line, it turns around and flies directly back to

the runner

What cumulative distance does the bird

travel? Even though the bird is a dodo, as-

sume that it occupies only one point in space

(a "zero" length bird). travels in a straight

line, and that it can turn without loss of

Speed

Answers

Answer:

7.53 km

Explanation:

We at given;

Speed of runner; v_r = 8.5 km/hr

Speed of bird; v_y = 17 km/hr

L = 6.4 km

We know that; time = distance/speed.

We are told that the bird starts from 6.4 km from the start and that it flies back to meet the runner after it reaches the finish line. If the total distance back to the runner is x, it means bird distance is 6.4 + (6.4 - x) = 12.8 - x

Thus;

Time of bird(t_y) = (12.8 - x)/17

Thus,

Time of runner(t_r) = x/8.5 hr

To find x, we have to equate the times of the runner and the bird.

Thus;

x/8.5 = (12.8 - x)/17

Multiply both sides by 17 to get;

2x = 12.8 - x

2x + x = 12.8

3x = 12.8

x = 12.8/3

x = 4.27 km

Thus, cumulative distance traveled by bird is; 12.8 - 4.27 = 7.53 km

Which of the following equations is balanced?

a. 2Al2O3 -----> 3Al + 3O2
b. 3Al2O3 -----> 3Al + 2O2
c. 2Al2O3 -----> 4Al + 3O2
d. 2Al2O3 -----> Al + 3O2

Answers

Answer: c

Explanation:

The way to check which one is the correct one is to simply multiply and see if there are the same number of atoms in both sides for each element.

a. 2×2 atoms of Al ≠ 3×1 atoms of Al

2×3 atoms of O = 3×2 atoms of O

BOTH MUST BE EQUAL FOR IT TO BE ADJUSTED!!!!!

b. 3×2 atoms of Al ≠ 3×1 atoms of Al

3×3 atoms of O ≠ 2×2 atoms of O

c. 2×2 atoms of Al = 4×1 atoms of Al

2×3 atoms of O = 3×2 atoms of O

BOTH ARE EQUAL, CORRECT ANSWER!!!

d. 2×2 atoms of Al ≠ 1×1 atoms of Al

2×3 atoms of O = 3×2 atoms of O

I need help, worth 40 Points!

A plane flies due north (90° from east) with a velocity of 100 km/h for 3 hours. During this time, a steady wind blows southeast at 30 km/h at an angle of 315° from due east. After 3 hours, where will the plane’s position be relative to its starting point?

*Please try to fill the data table.

Answers

Answer:

thank you

Explanation:

Split up the two given velocity vectors into horizontal and vertical components.

Plane:

p = (100 km/h) (cos(90°) i + sin(90°) j ) = (100 km/h) j

Its direction is given, 90° relative to east.

Traveling for 3 hours with this velocity results in a displacement of

p * (3 h) = (300 km/h) (3h) j = (900 km) j

meaning that this velocity contributes to a north-facing displacement of 900 km.

Wind:

w = (30 km/h) (cos(315°) i + sin(315°) j ) ≈ (21.2 km/h) i + (-21.2 km/h) j

Its direction is also given, 315° relative to east.

After 3 h, this velocity contributes to a displacement of

w * (3h) ≈ (63.6 km) i + (-63.6 km) j

meaning if the plane had no velocity of its own but somehow stayed in the air, the wind would have pushed it about 63.6 km south and 63.6 km east, which translates to a net displacement of

√((63.6 km)² + (-63.6 km)²) = 90 km

due southeast.

Putting everything together, your table displacement table should read:

.                       |   wind   |   plane

velocity           |   30      |   100       ...   km/h

direction         |   90°     |   315°      ...   relative to east

x                      |   63.6   |   0           ...   km

y                      |  -63.6   |   900      ...   km

The resultant vector is the sum of these, r = p + w :

r ≈ (21.2 km/h) i + (78.8 km/h) j

After 3 h, the resultant displacement is

r * (3h) ≈ (63.6 km) i + (236.4 km) j

with magnitude

√((63.6 km)² + (236.4 km)²) ≈ 244.8 km

and direction θ such that

tan(θ) ≈ (236.4 km) / (63.6 km)

θ ≈ arctan(3.714) ≈ 74.9°

So the resultant table should read

xnet             |   63.6 km

ynet             |   236.4 km

magnitude   |   244.8 km

theta            |   74.9° relative to east

Please help me fast

Answers

Answer:

b I think. sorry if it's wrong

A submarine is built to dive to a depth of 90 m where the pressure in the water is about 1 MPa. The engineers want to build a window in the submarine, but the window can only take a force of 10 kN safely. What is the largest surface area window that can be used?

Answers

Answer:

The largest surface area window that can be used is [tex]A=0.01\ m^2[/tex]

Explanation:

Pressure

The pressure is defined as force per unit area. The SI unit for pressure is the Pascal (Pa), defined as Newton per square meter.

If a force F acts on a surface area A, the pressure is calculated as:

[tex]\displaystyle P=\frac{F}{A}[/tex]

The pressure at a depth of 90 m is P=1 Mpa= 1,000,000 Pa and the submarine's window can only take a force of F=10 kN=10,000 N.

We need to calculate the largest surface area of the window. We can solve the equation for A:

[tex]\displaystyle A=\frac{F}{P}[/tex]

Substituting:

[tex]\displaystyle A=\frac{10,000}{1,000,000}[/tex]

[tex]A=0.01\ m^2[/tex]

The largest surface area window that can be used is [tex]\mathbf{A=0.01\ m^2}[/tex]

Can someone Plzzz help meee.

Answers

solid...............

what is electricity

Answers

Answer:

Electricity is the flow of electrical power or charge. It is a secondary energy source which means that we get it from the conversion of other sources of energy, like coal, natural gas, oil, nuclear power and other natural sources, which are called primary sources.

On Planet X, an astronaut has maximum walking speed of 1.9 m/s. The astronaut's legs are each 1.3 m long. What is the constant of acceleration due to gravity on Planet X?

A. 8.3 m/s2
B. 2.8 m/s2
C. 3.8 m/s2
D. 1.1 m/s2

Answers

Answer:

Acceleration due to Gravity:

Explanation:

Here g is acceleration due to gravity. So C. 3.8 m/s2

Classify each resource as renewable or nonrenewable.

Answers

Answer:

coal: nonrenewable

geothermal energy: renewable

wind: renewable

natural gas: nonrenewable

Explanation:

Have a good day

Thanks

Answer:

coal is non-renewable, the wind is renewable, I belive natural gas is not but I'm not to sure with that one. geothermal energy is renewable.

Explanation:

List the three astronomical causes for the seasons

Answers

1. Is the Earth’s tilted axis

11. The professor who first

implemented a scientific approach in

order to investigate a problem, and

who is often referred to as ‘the father

of scientific methodology’, is:

a. Galileo

b. Democritus

c. Newton

d. Einstein

12. Which of the following adjustments

to a pendulum would affect the

period of oscillation?

a. Increasing the mass

b. Decreasing the length

c. Increasing the length

d. Increasing the angle of

displacement

13. The width of a desk was measured

using a meter ruler, which of the

following is the most appropriate

reading expressing the result?

a. 0.724 m

b. 0.7248 m

c. 0.72 m

d. 72 cm​

Answers

Answer:Newton

Explanation:

Lead-202 has a half-life of 53,000 years. How long will it take for 15/16 of a sample of lead-202 to decay?
106,000 years
159,000 years
212,000 years
265,000 years
(Thank you very much :L)

Answers

Answer:

C. 212,000 years

Explanation:

believe me it's correct.....and you're welcome :)

for which colour of light is. the index of refraction of glass largest​

Answers

Answer:

don't know sorry for the irreverent answer..

Answer:

The index of refraction varies with frequency, it doesn't change as light travels from one medium to another, As violet colour has the shortest wavelength and so the refractive index is maximum for it.

A sample contains 20 kg of radioactive material. The decay constant of the material is 0.179 per second. If the amount of time that has passed
is 300 seconds, how much of the of the original material is still radioactive? Show all work

Answers

Answer:

There are [tex]9.537\times 10^{-23}[/tex] kilograms of radioactive material after 300 seconds.

Explanation:

From Physics we know that radioactive materials decay at exponential rate, whose differential equation is:

[tex]\frac{dm}{dt} = -\lambda\cdot m[/tex] (1)

Where:

[tex]\frac{dm}{dt}[/tex] - Rate of change of the mass of the radioactive material, measured in kilograms per second.

[tex]m[/tex] - Current mass of the radioactive material, measured in kilograms.

[tex]\lambda[/tex] - Decay constant, measured in [tex]\frac{1}{s}[/tex].

The solution of the differential equation is:

[tex]m(t) = m_{o}\cdot e^{-\lambda\cdot t}[/tex] (2)

Where:

[tex]m_{o}[/tex] - Initial mass of the radioactive material, measured in kilograms.

[tex]t[/tex] - Time, measured in seconds.

If we know that [tex]m_{o} = 20\,kg[/tex], [tex]\lambda = 0.179\,\frac{1}{s}[/tex] and [tex]t = 300\,s[/tex], then the initial mass of the radioactive material is:

[tex]m(t) = (20\,kg)\cdot e^{-\left(0.179\,\frac{1}{s} \right)\cdot (300\,s)}[/tex]

[tex]m(t) \approx 9.537\times 10^{-23}\,kg[/tex]

There are [tex]9.537\times 10^{-23}[/tex] kilograms of radioactive material after 300 seconds.

A diver runs horizontally off the end of a diving board with an initial speed of 1.95 m/s. If the diving board is 2.00 m above the water, what is the diver's speed just before she enters the water

Answers

Answer:

V = 6.56 m/s

Explanation:

in order to find the speed of the diver before she enters we need to find the vertical component of its final velocity by using 3rd equation of motion:

2gh = Vy² - V₀y²

where,

g = 9.8 m/s²

h = height = 2 m

Vy = Vertical Component of Final Velocity = ?

V₀y = Vertical Component of Initial Velocity = 0 m/s

Therefore,

2(9.8 m/s²)(2 m) = Vy² - (0 m/s)²

Vy = √39.2 m²/s²

Vy = 6.26 m/s

Assuming negligible air friction, the x-component of the final velocity will be the same as the initial velocity:

Vₓ = V₀ₓ = 1.95 m/s

Hence, the final velocity will be:

V = √(Vₓ² + Vy²)

V = √[(1.95 m/s)² + (6.26 m/s)²]

V = 6.56 m/s

The components of a 15-meters-per-second velocity at an angle of 60.° above the horizontal are (1) 7.5 m/s vertical and 13 m/s horizontal (2) 13 m/s vertical and 7.5 m/s horizontal (3) 6.0 m/s vertical and 9.0 m/s horizontal (4) 9.0 m/s vertical and 6.0 m/s horizontal

Answers

Answer:

13 m/s vertical and 7.5 m/s horizontal

Explanation:

❤️

The vertical and horizontal components of a projectile is required.

The correct option is (2) 13 m/s vertical and 7.5 m/s horizontal

u = Initial velocity of projectile = 15 m/s

[tex]\theta[/tex] = Angle of projectile = [tex]60^{\circ}[/tex]

The horizontal component

[tex]u_x=u\cos \theta\\\Rightarrow u_x=15\cos60^{\circ}\\\Rightarrow u_x=7.5\ \text{m/s}[/tex]

The vertical component

[tex]u_y=u\sin \theta\\\Rightarrow u_x=15\sin60^{\circ}\\\Rightarrow u_x=13\ \text{m/s}[/tex]

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What is an electromagnetic wave?

A. An induced electric current
B. Vibrating electric and magnetic fields
C. Oscillating electric current
D. An electromagnet

Answers

I think it is B. Sorry if I’m wrong

2. An object is moving with an initial velocity of 12 m/s. It accelerates at a rate of 1.5 m/s^2 over a distance of 40 m. What is its new velocity?

Answers

Answer:

16.2 m/s

Explanation:

2ad=Vf^2-Vi^2

2 (1.5) (40) = Vf^2 -(12)^2

Vf= 16.2 m/s

When an 8 V battery is connected to a resistor, a 2 A current flows in the resistor. What is the resistor's value?
Ο Α. 2Ω
Ο Β. 4 Ω
Ο C. 8Ω
Ο D. 16 Ω

Answers

Answer:

B

Explanation:

V=IR    I= curren V=volt R=resistor

8=2.R   8/2=R R=4

A bugatti chiron travels 116 m/s for 10 seconds.how far did it travel

Answers

Answer:

V=  1,160 m

Explanation:

formula:

            V=  V*  T

remplazamos:

V= 116m /s * 10s

V=  1,160 m

Answer:

V=  1,160 m

Explanation:

Please identify the type of inference happening at letter A and the type of interference happening at letter B. If this was a sound wave, which (A or B) do you think would be louder and why?

Answers

Answer:

B i think

Explanation:

B because it travels in the same wavelentgh.............

[tex]gjkrejktg[/tex]

Type A is constructive interference and Type B wave gives destructive interference. The constructive interference would be louder.

What is interfernece?

Interference can be described as a natural phenomenon that occurs at every place and at every moment. Interference can be defined as the phenomenon in which two waves superpose to produce the resultant wave of the lower, higher, or same amplitude. Light waves are produced randomly by most of the sources.

The interference of light from the soap bubble which reflects colors when illuminated by a light source. The starting point of the wave produced may be a maximum or a minimum,  and there is no way to predict which phase the wave will start.

Interference can either be constructive interference or destructive interference. Constructive interference occurs when the crest of one wave falls on the crest of another wave and the amplitude is maximum.

In destructive interference, when the crest of one wave falls on the trough of another wave and the amplitude is minimum. The phase and displacement of these waves are not the same.

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What would be the y-component of a velocity vector that had a
magnitude of 37m/s in a direction 30° from the x-axis?

Answers

Answer:

18.5 m/s

Explanation:

Just did it on EdPuzzle

The y-component of a velocity vector that had a magnitude of 37 m / s in a direction 30° from the x - axis would be 18.5 m / s .

What is a vector quantity?

The quantities that contain the magnitude of the quantities along with the direction are known as the vector quantities.

Examples of vector quantities are displacement, velocity acceleration, force, etc.

As given in the problem we have to find out the y-component of a velocity vector that had a magnitude of 37 m / s in a direction 30° from the x - axis.

The y-component of a velocity vector = 37 × sin 30

                                                                   = 18.5 m / s

Thus , y-component of a velocity vector that had a magnitude of 37 m / s in a direction 30° from the x - axis would be 18.5 m / s.

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Opal is making a list of the uses of electromagnetic radiation. Which of the following should Opal NOT include in her list?

A. A man using a microwave to boil water

B. A submarine using sonar to locate a ship

C. A girl using a remote control to change television channels

D. A hospital using an X-ray machine to take a picture of a broken bone

Answers

Answer:

A.

Explanation:

A man using a microwave to boil water

Answer:

d

Explanation:

A roller coaster is travelling 1 m/s at the top of the track. At the bottom of the track, 5 seconds later, it is travelling 36 m/s. What is the average acceleration?

7.2 m/s2
0.14 m/s2
36 m/s 2
7 m/s2

Answers

Answer:

7m/s²

Explanation:

Given parameters:

Velocity at the top = 1m/s

Velocity at the bottom  = 36m/s

Time  = 5s

Unknown:

Average acceleration = ?

Solution;

Acceleration is the rate of change of velocity with time. It is expressed as;

  A = [tex]\frac{v -u}{t}[/tex]

v is the velocity at the top

u is the velocity at the bottom

t is the time taken

 Now, insert the parameters and solve;

  A = [tex]\frac{36 - 1}{5}[/tex]   = 7m/s²

The average acceleration will be "7 m/s²".

Given values:

Top velocity,

v = 1 m/s

Bottom velocity,

u = 36 m/s

Time,

t = 5 s

The acceleration is:

→ [tex]A = \frac{v -u}{t}[/tex]

By putting the values,

       [tex]= \frac{36-1}{5}[/tex]

       [tex]= \frac{35}{5}[/tex]

       [tex]= 7 \ m/s^2[/tex]

Thus the answer above i.e., "option d" is correct.

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A person with a weight of 120 lbs. is standing on a scale. What force is the
scale exerting on the person? *
O Olbs up
O 60 lbs up
O 120 lbs up
240 lbs up

Those 4 numbers are the answer choices plz help

Answers

Answer:

The answer is 120lbs

Explanation:

because the scale exerts enough force to equal out to 0 and since the person is putting 120lbs onto the scale it then pushes back enough force to keep them up

The upward force acting on the body is 534 N which is equal to 240 lbs in the upward direction, hence, option d is correct.

What is force?

Force is an external agent acting on a body to change it from the state of motion or rest. There are various kind of forces namely, gravitational force, magnetic force, nuclear force etc.

Gravitational force is the force by which an object  attracts other objects to its center of mass. Gravitational force depends on the  mass of the object and the distance from the surface of earth.

The weight of the person is 120 lbs.

1 Kg = 2.2 lbs

120 lbs = 54.5 Kg.

The force acting on the body by their weight =  mg = 54.5 Kg × 9. 8 m/s².

= 534 N.

Hence, 534 N is  240 lbs  (534 /2.2 ) of force upward.

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The average velocity of an object over 6.0 seconds interval is 2 m/s what is the total distance traveled and M by the object doing this time interval

Answers

Answer:

The answer is 12 m

Explanation:

The distance covered by an object given it's velocity and time taken can be found by using the formula

distance = velocity × time

From the question we have

distance = 2 × 6

We have the final answer as

12 m

Hope this helps you



A car drives 400 meters in 5 seconds. What is the cars speed in m/s?

Answers

Answer:

80/1

Explanation:

to figure out the answer of how many miles/meters per second divide the meters/miles by the second

so 400÷5 would be 80

80 meters per second

hope this helps :))

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