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2 years ago

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A wagon full of manure accidentally rolls down a driveway for 5.0m while a person pushes against the wagon with a force of 420 N

to bring it to a stop. What is the change in kinetic energy for the wagon?

2 answers:

Cerrena [4.2K]2 years ago

8 0

Answer:

2100 J

Explanation:

Parameters given:

Force acting on the object, F = 420 N

Distance moved by object, d = 5m

The change in kinetic energy of an object is equal to the work done by a force acting on the object:

W = F * d

∆KE = F * d

∆KE = 420 * 5

∆KE = 2100 J

Studentka2010 [4]2 years ago

6 0

Answer:

∆KE = 2100 J

Explanation:

Given:

Force of person pushes against the wagon= F = 420 N

Distance = d = 5.0 m

When you accelerate an object, you are doing work against inertia. It is proven that work equals the change in kinetic energy of the object.

therefore, W = ΔKE

where,

W is the work done against the resistance of inertia

ΔKE is the change in kinetic energy (Δ is Greek letter capital delta)

Also, W = F x d

∴∆KE = F x d

∆KE = 420 x 5

∆KE = 2100 J

The change in kinetic energy for the wagon is 2100 J

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stealth61 [152]

Answer:

W = 9533.09 Watt

Explanation:

given,

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head upto water level is to rise = 60 + 5

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we know

A₁ v₁ = A₂ v₂ = Q

π r₁² v₁ = π r₂² v₂ = 0.015

$v_1= \dfrac{r_2^2}{r_1^2} v_2$

$v_1= \dfrac{7.5^2}{5^2} v_2$

$v_1= 2.25 v_2$

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$v_2 = \dfrac{0.015}{\pi 0.075^2}$

v₂ = 0.848 m/s

v₁ = 1.908 m/s

Applying Bernoulli's equation

$P_p = \dfrac{1}{2}\rho (v_2^2-v_1^2)+ \rho g h$

$P_p= \dfrac{1}{2}\times 1000\times (0.848^2-1.908^2)+ 1000\times 9.8\times 65$

$P_p= 635539.32 Pa$

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2 years ago

In a study, the data you collect is Habits on a Always/Sometimes/Never scale.What is the level of measurement?

zzz [600]

Answer:

Ordinal

Explanation:

There are four levels of measurement which include the nominal, ordinal, interval, and ratio. The data collected above is ordinal data as it qualifies the data and still indicates the ordering of the data. It gives the observer an idea of the range of data collected or its rating although mathematical calculations may not be done with it.

The other forms of data include the nominal which simply qualifies the data, the interval which qualifies the data but which the differences between the data can be obtained, and of course the data has no starting point. The ratio scale which is similar to the interval scale but which the ratios between the data obtained can be compared.

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2 years ago

A 6.0-cm-diameter, 11-cm-long cylinder contains 100 mg of oxygen (O2) at a pressure less than 1 atm. The cap on one end of the c

g100num [7]

Explanation:

The given data is as follows.

Mass of oxygen present = 100 mg = $100 \times 10^{-3}$ g

So, moles of oxygen present are calculated as follows.

n = $\frac{100 \times 10^{-3}}{32}$

= $3.125 \times 10^{-3}$ moles

Diameter of cylinder = 6 cm = $6 \times 10^{-2}$ m

= 0.06 m

Now, we will calculate the cross sectional area (A) as follows.

A = $\pi \times \frac{(0.06)^{2}}{4}$

= $2.82 \times 10^{-3} m^{2}$

Length of tube = 11 cm = 0.11 m

Hence, volume (V) = $2.82 \times 10^{-3} \times 0.11$

= $3.11 \times 10^{-4} m^{3}$

Now, we assume that the inside pressure is P .

And, $P_{atm}$ = 100 kPa = 100000 Pa,

Pressure difference = 100000 - P

Hence, force required to open is as follows.

Force = Pressure difference × A

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We are given that force is 173 N.

Thus,

$(100000 - P) \times 2.82 \times 10^{-3}$ = 173

Solving we get,

P = $3.8650 \times 10^{4} Pa$

= 38.65 kPa

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So, we will put the values into the above formula as follows.

PV = nRT

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2 years ago

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Answer:

1) A. 0.44 m/s East + 0.33 m/s North

2) A. 0 m/s²

3) A. a scalar calculated as distance divided by time.

4) B. 31 km per hour

Explanation:

1) Velocity is DISPLACEMENT over time.

at 1 m/s, total time of walking is 9000 seconds

displacement is 3000 m north and 5000 - 1000 = 4000 m east

4000 m/ 9000 s = 0.44 m/s E

3000 m/ 9000s = 0.33 m/s N

2) constant speed means no acceleration

3) A. a scalar calculated as distance divided by time.

4) displacement 50 km N and 80 km W

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3 0

1 year ago

A rock is rolling down a hill. At position 1, it’s velocity is 2.0 m/s. Twelve seconds later, as it passes position 2, it’s velo

mr Goodwill [35]

Answer

Hi,

correct answer is {D} 3.5 m/s²

Explanation

Acceleration is the rate of change of velocity with time. Acceleration can occur when a moving body is speeding up, slowing down or changing direction.

Acceleration is calculated by the equation =change in velocity/change in time

a= {velocity final-velocity initial}/(change in time)

a=v-u/Δt

The units for acceleration is meters per second square m/s²

In this example, initial velocity =2.0m/s⇒u

Final velocity=44.0m/s⇒v

Time taken for change in velocity=12 s⇒Δt

a= (44-2)/12 = 42/12

3.5 m/s²

Best Wishes!

5 0

2 years ago