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
aivan3 [116]
3 years ago
15

The kinetic energy of a moving object is E=12mv2. A 61 kg runner is moving at 10kmh. However, her speedometer is only accurate t

o within 0.1kmh. What is the potential error in her calculated kinetic energy, as a result of the imprecision in the measurement of her velocity?
Physics
1 answer:
jek_recluse [69]3 years ago
4 0

Answer:

e=3367.2J

%e=1.43%

Explanation:

From the exercise we know two information. The real speed and the experimental measured by the speedometer

v_{r}=10km/h=2.77m/s

Since the speedometer is only accurate to within 0.1km/h the experimental speed is

v_{e}=10km/h-0.1km/h=9.9km/h=2.75m/s

Knowing that we can calculate Kinetic energy for the real and experimental speed

E_{r}=\frac{1}{2}mv^2=\frac{1}{2}(61000g)(2.77m/s)^2=234023J

E_{e}=\frac{1}{2}mv^2=\frac{1}{2}(61000g)(2.75m/s)^2=230656J

Now, the potential error in her calculated kinetic energy is:

e=E_{r}-E_{e}=(234023-230656)J=3367.2J

%e=\frac{E_{r}-E_{e}}{E_{r}}x100=\frac{(234023-230656)J}{234023J}x100=1.43%

You might be interested in
Un cubo de madera de densidad 0.780 g/cm³ mide 11.2 cm en un lado. Cuando se coloca en agua, ¿qué altura del bloque flotará sobr
Stolb23 [73]

Answer:

2.464 cm above the water surface

Explanation:

Recall that for the cube to float, means that the volume of water displaced weights the same as the weight of the block.

We calculate the weight of the block multiplying its density (0.78 gr/cm^3) times its volume (11.2^3  cm^3):

weight of the block = 0.78 * 11.2^3  gr

Now the displaced water will have a volume equal to the base of the cube (11.2 cm^2) times the part of the cube (x) that is under water. Recall as well that the density of water is 1 gr/cm^3.

So the weight of the volume of water displaced is:

weight of water = 1 * 11.2^2 * x

we make both weight expressions equal each other for the floating requirement:

0.78 * 11.2^3 = 11.2^2 * x

then x = 0.78 * 11.2 cm = 8.736 cm

This "x" is the portion of the cube under water. Then to estimate what is left of the cube above water, we subtract it from the cube's height (11.2 cm) as follows:

11.2 cm - 8.736 cm = 2.464 cm

6 0
3 years ago
Ross, a college sophomore, has no clear preference for any of the candidates running for student body president. The students he
mylen [45]

Answer:

longing for social inclusion.

Explanation:

Ross here is longing for social inclusion.

He decides to campaign for the his fraternity brother not by choice or will but by peer pressure and social inclusion because most of the students campaigned for Henry so he supports Henry as well. Moreover, he did not be feel left out and he did not have a clear preference as well.

7 0
3 years ago
A large lightning bolt consists of a 18.2~\text{kA}18.2 kA current that moved 30.0~\text{C}30.0 C of charge. Assuming a constant
marissa [1.9K]

Answer:

1.65\times {-3} \text { s}

Explanation:

Current is the rate of flow of charge.

I=\dfrac{Q}{t}

t = \dfrac{Q}{I}

t = \dfrac{30.0}{18.2\times10^3} =1.65\times {0-3} = 1.65\times {-3} \text { s}

6 0
2 years ago
Read 2 more answers
A closed system:
adoni [48]
The answer is b i just did the test
3 0
2 years ago
This question is related to inertia:
luda_lava [24]
The way I do it is suddenly, in the same sort of way that magicians try to pull a table cloth off a table when there's things on the table cloth.The sudden approach acts as an impulse of force and starts to accelerate the roll. But, the piece (assuming it has perforations) is off the roll before the roll can move, due to inertia. Then the roll will acclerate, move, slow down and stop. However, in accelerating, the roll will unravel. The bigger the impulse the more it will unravel.+++++++++++++++++++++++++++++++++++++++If on the other hand, the piece of paper is held firmly, and the roll is pulled, then the impulse is presumably given to the paper and the hand whose inertia is a lot more than that of the roll. So, I think I'd actually go for choice c)+++++++++++++++++++++++++++++++++++++This assumes that the roll is free to rotate.I think that a similar idea is behind the design and use of a "ballistic galvanometer". The charge is passed through the galvanometer quickly, as a current pulse. Then the needle starts to deflect, and the deflection is arranged to depend on the total charge that has passed through in the time of the current pulse.
3 0
3 years ago
Other questions:
  • Time period from one noon to the next
    9·1 answer
  • Which of the following components of an electrical circuit is a source of voltage?
    10·2 answers
  • A substance has a melting point of 800ºC and a boiling point of 1465ºC. The substance is most likely
    6·1 answer
  • The tent meteorite, found in 1897 near cape York, on the west coast of Greenland, is the largest meteorite exhibited by any muse
    8·1 answer
  • 1) Two cars both moving at 27m/s (60mile/hr) pass each other on a road, one moving east the othe other west. 1a) both cars have
    13·1 answer
  • Which object would have a LARGER gravitational force acting upon it? (assume the objects are at the same height above the Earth.
    12·2 answers
  • The melting of glaciers and the polar ice caps poses a devastating threat of potential flooding for low-lying areas. Scientists
    14·1 answer
  • If the displacement of a horizontal mass-spring system was doubled, the elastic potential energy in the system would change by a
    8·1 answer
  • A shopper walks eastward 5.4 meters, then walks westward 7.8 meters eastward
    13·1 answer
  • Can you get cool powers.
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!