1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
mr_godi [17]
3 years ago
7

A 1890 kg truck traveling north at 34 km/h turns east and accelerates to 62 km/h. (a) What is the change in the truck's kinetic

energy
Physics
1 answer:
rodikova [14]3 years ago
3 0

Answer:

<h2>2540.18 kJ</h2>

Explanation:

The change in the trucks kinetic energy is same as the net work done by the truck in covering the said distance

Given data

mass of truck m= 1890 kg

initial velocity of truck u1= 34 km/h

final velocity v1= 62 km/h

applying the kinetic energy formula we have

K.E= \frac{1}{2}mv^2

K.E(initial)

K.E(initial)= \frac{1}{2}*1890*34^2\\\\ K.E(initial)= \frac{1}{2}*1890*1156\\\\ K.E(initial)= \frac{1}{2}*2184840\\\\ K.E(initial)= 1092420J\\\\\ K.E(initial)= 1092.4kJ

K.E(final)

K.E(initial)= \frac{1}{2}*1890*62^2\\\\ K.E(initial)= \frac{1}{2}*1890*3844\\\\ K.E(initial)= \frac{1}{2}*7265160\\\\ K.E(initial)= 3632580J\\\\\ K.E(initial)= 3632.58kJ

The change in K.E= K.E(final)- K.E(initial) = 3632.58-1092.4= 2540.18 kJ

<em><u>the change in the truck's K.E is 2540.18 kJ</u></em>

You might be interested in
A student practicing for a cross country meet runs 250 m in 30 s. What is the average speed
Kaylis [27]

Answer:8.3m/sec 30 sec,

Explanation:

A student practicing for a track meet, ran 250 m in 30 sec. a. What was her average speed? 250 m = 8.3 m/sec 30 sec.

5 0
3 years ago
Read 2 more answers
A train’s mass is 18181.81 kg. What is its weight?
wel

Answer:

The trains mass in pounds would be 40084.029 if you would round it to the hundreths

Explanation:

7 0
3 years ago
Read 2 more answers
Determine the capacitive reactance for a 20 uF capacitor that is across a 20 volt, 60 Hz source
aleksandr82 [10.1K]

Answer:

Capacitive reactance is 132.6 Ω.

Explanation:

It is given that,

Capacitance, C=20\ \mu F=20\times 10^{-6}\ F=2\times 10^{-5}\ F

Voltage source, V = 20 volt

Frequency of source, f = 60 Hz

We need to find the capacitive reactance. It is defined as the reactance for a capacitor. It is given by :

X_C=\dfrac{1}{2\pi fC}

X_C=\dfrac{1}{2\pi \times 60\ Hz\times 2\times 10^{-5}\ F}

X_C=132.6\ \Omega

So, the capacitive reactance of the capacitor is 132.6 Ω. Hence, this is the required solution.

4 0
3 years ago
Calculate the specific heat at constant volume of water vapor, assuming the nonlinear triatomic molecule has three translational
vampirchik [111]

Answer:

I) c=1385.667\frac{J}{kg K}

II)The difference from the value obtained on part I is: 2000-1385.67 =614.33 \frac{J}{Kg K}

The possible reason of this difference is that the vibrational motion can increase the value, since if we take in count this factor we will have a higher heat capacity, because molecules with vibrational motion require more heat to vibrate and necessary higher specific heat capacity.

Explanation:

From the problem we have the molar mass given M=18\frac{gr}{mol} of water vapor and at constant volume condition. It's important to say that the vapour molecules have 3 transitionsl and 3 rotational degrees of freedom and the rotational motion no contribution.

Part I

Calculate the specific heat at constant volume of water vapor, assuming the nonlinear triatomic molecule has three translational and three rotational degrees of freedom and that vibrational motion does not contribute. The molar mass of water is 18.0 g/mol=0.018kg/mol.

Let C_v (\frac{J}{Kg K}) the molar heat capacity at constant volume and this amount represent the quantity of heat absorbed by mole.

Let C (\frac{J}{Kg K}) the specific heat capcity this value represent the heat capacity aboserbed by mass.

For the problem we have a total of 6 degrees of freedom and from the thoery we know that for each degree of freedom the molar heat capacity at constant volume is given by C_v =\frac{R}{2} so the total for the 6 degrees of freedom would be:

C_v =6*\frac{R}{2}=3R=3x8.314\frac{J}{mol K}=24.942\frac{J}{mol K}

And by definition we know that the specific heat capacity is defined:

c=\frac{C_V}{M}

If we replace all the values we have:

c=\frac{24.942\frac{J}{mol K}}{0.018\frac{kg}{mol}}=1385.667\frac{J}{kg K}

So on this case the specific heat capacity with constant volume and with three translational and three rotational degrees of freedom is c=1385.667\frac{J}{kg K}

Part II

The actual specific heat of water vapor at low pressures is about 2000 J/(kg * K). Compare this with your calculation.

The difference from the value obtained on part I is: 2000-1385.67 =614.33 \frac{J}{Kg K}

The possible reason of this difference is that the vibrational motion can increase the value, since if we take in count this factor we will have a higher heat capacity, because molecules with vibrational motion require more heat to vibrate and necessary higher specific heat capacity.

4 0
4 years ago
A baseball has a mass of 0.15 kg and radius 3.7 cm. In a baseball game, a pitcher throws the ball with a substantial spin so tha
mylen [45]

Answer:

Rotational kinetic energy = 0.099 J

Translational kinetic energy = 200 J

The moment of inertia of a solid sphere is I = \frac{2}{5}mr^2.

Explanation:

Rotational kinetic energy is given by

\text{RKE} = \frac{1}{2}I\omega^2

where <em>I</em> is the moment of inertia and <em>ω</em> is the angular speed.

For a solid sphere,

I = \frac{2}{5}mr^2

where <em>m</em> is its mass and <em>r</em> is its radius.

From the question,

<em>ω</em> = 49 rad/s

<em>m</em> = 0.15 kg

<em>r</em> = 3.7 cm = 0.037 m

\text{RKE} = \frac{1}{2}\times \frac{2}{5} mr^2\omega^2 = \frac{1}{5} mr^2\omega^2

\text{RKE} = \frac{1}{5} (0.15\ \text{kg})(0.037\ \text{m})^2(49\ \text{rad/s})^2 = 0.099\text{ J}

Translational kinetic energy is given by

\text{TKE} = \frac{1}{2} mv^2

where <em>v</em> is the linear speed.

\text{TKE} = \frac{1}{2} (0.15\ \text{kg})(52\ \text{m/s})^2 = 200\text{ J}

5 0
3 years ago
Read 2 more answers
Other questions:
  • A heat engine does 9200 J of work per cycle while absorbing 22.0 kcal of heat from a hightemperature reservoir. What is the effi
    15·1 answer
  • Astronomers estimate that a galaxy contains a. 100 stars. c. millions or billions of stars. b. 1 star. d. 100,000 stars.
    14·1 answer
  • Using a rope that will snap if the tension in it exceeds 356 N, you need to lower a bundle of old roofing material weighing 478
    8·1 answer
  • If the forces acting on an object are balanced, the object may change speed, change direction, or do both. true or false please
    7·1 answer
  • Which statement best describes the kinetic theory of matter?
    14·2 answers
  • A box is being pushed across the floor at a constant velocity with an
    12·1 answer
  • Use the law of conservation of energy to explain why the work output of a machine can never exceed the work input
    7·2 answers
  • The sympathetic nervous system ____________digestion and _____________blood pressure. (2 points)
    6·1 answer
  • An object moving at a constant velocity will always have a
    10·2 answers
  • Particle A of charge 2.76 10-4 C is at the origin, particle B of charge -6.54 10-4 C is at (4.00 m, 0), and particle C of charge
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!