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
vovangra [49]
2 years ago
5

Very large accelerations can injure the body, especially if they last for a considerable length of time. The severity index (SI)

, a measure of the likelihood of injury, is defined as SI = a5/2t, where a is the acceleration in multiples of g and t is the time the acceleration lasts (in seconds). In one set of studies of rear end collisions, a person's velocity increases by 12 km/h with an acceleration of 35 m/s2.(a) What is the severity index for the collision? (s)(b) How far does the person travel during the collision if the car was initially moving forward at 7.0 km/h? (m)
Physics
1 answer:
Ludmilka [50]2 years ago
8 0

Answer:

a) The severity index (SI) is 3047.749, b) The injured travels 0.345 meters during the collision.

Explanation:

a) The g-multiple of the acceleration, that is, a ratio of the person's acceleration to gravitational acceleration, is:

a' = \frac{35\,\frac{m}{s^{2}} }{9.807\,\frac{m}{s^{2}} }

a' = 3.569

The time taken for the injured to accelerate to final speed is given by this formula under the assumption of constant acceleration:

v_{f} = v_{o} + a \cdot t

Where:

v_{o} - Initial speed, measured in meters per second.

v_{f} - Final speed, measured in meter per second.

a - Acceleration, measured in \frac{m}{s^{2}}.

t - Time, measured in seconds.

t = \frac{v_{f}-v_{o}}{a}

t = \frac{\left(12\,\frac{km}{h} \right)\cdot \left(1000\,\frac{m}{km} \right)\cdot \left(\frac{1}{3600}\,\frac{h}{s}  \right)}{35\,\frac{m}{s^{2}} }

t = 0.095\,s

Lastly, the severity index is now determined:

SI = \frac{a'^{5}}{2\cdot t}

SI = \frac{3.569^{5}}{2\cdot (0.095\,s)}

SI = 3047.749

b) The initial and final speed of the injured are 1.944\,\frac{m}{s} and 5.278\,\frac{m}{s}, respectively. The travelled distance can be determined from this equation of motion:

v_{f}^{2} = v_{o}^{2} + 2\cdot a \cdot \Delta s

Where \Delta s is the travelled distance, measured in meters.

\Delta s = \frac{v_{f}^{2}-v_{o}^{2}}{2\cdot a}

\Delta s = \frac{\left(5.278\,\frac{m}{s} \right)^{2}-\left(1.944\,\frac{m}{s} \right)^{2}}{2\cdot \left(35\,\frac{m}{s^{2}} \right)}

\Delta s = 0.345\,m.

You might be interested in
With the same block-spring system from above, imagine doubling the displacement of the block to start the motion. By what factor
Fofino [41]

Answer:

A)     K / K₀ = 4   b)     v / v₀ = 4

Explanation:

A) For this exercise we can use the conservation of mechanical energy

in the problem it indicates that the displacement was doubled (x = 2xo)

starting point. At the position of maximum displacement

      Em₀ = Ke = ½ k (2x₀)²

final point. In the equilibrium position

      Em_{f} = K = ½ m v²

        Em₀ = Em_{f}

        ½ k 4 x₀² = K

        (½ K x₀²) = K₀

         K = 4 K₀

          K / K₀ = 4

B) the speed value

          ½ k 4 x₀² = ½ m v²

          v = 4 (k / m) x₀

if we call

           v₀ = k / m x₀

          v = 4 v₀

         v / v₀ = 4

3 0
2 years ago
Small paragraph explaining how how potential and kinetic energy are related
weeeeeb [17]

Answer:

Kinetic energy is energy possessed by a body by virtue of its movement. Potential energy is the energy possessed by a body by virtue of its position or state. While kinetic energy of an object is relative to the state of other objects in its environment, potential energy is completely independent of its environment.

Explanation:

4 0
3 years ago
Read 2 more answers
In the chemical equation above, the small number after the O in 1202 represent —
Murrr4er [49]

Answer:

G.) The number atoms of that element in the molecule

Explanation:

F is incorrect because the coefficient represents the amount of one type of molecule, not the subscript

G is correct because subscripts represent how many atoms of that element are present in that single molecule

H is incorrect because energy is not represented in this simple type of equation

J is incorrect because it doesn't even make sense

7 0
2 years ago
In the diagnostic radiology energy range (which includes mammography) from 23 to 150 kVp, which of the following tissues possess
Semmy [17]

Answer:

Bone

Explanation:

Diagnostic radiology include the use of non-invasive imaging scans to diagnose a patient.

The voltages used in diagnostic tubes range from roughly 20 kV to 150 kV and thus the highest energies of the X-ray photons range from roughly 20 keV to 150 keV.

The tests and equipment used sometimes involves low doses of radiation to create highly detailed images of an area.

4 0
2 years ago
You decide to ride your bike for 30 minutes, raising your heart rate to the middle of your target heart rate zone. What type of
a_sh-v [17]
It would have to be cardio i think not totally sure
4 0
3 years ago
Read 2 more answers
Other questions:
  • What kind of radiation is stopped by a piece of paper
    7·2 answers
  • A water wave has a frequency of 2 HZ and a wavelength of 5 meters what is its speed
    12·1 answer
  • A solution with a pH of 7 is
    10·2 answers
  • All of the planets stay near the ecliptic as they move on the Celestial Sphere
    14·1 answer
  • Power is expressed in ________?
    14·1 answer
  • In 2007, michael carter (u.s.) set a world record in the shot put with a throw of 24.77 m. what was the initial speed of the sho
    13·1 answer
  • If the effects of heat and friction are ignored, the amount of work output is always _______ the amount of work input, even when
    7·1 answer
  • Which of the following objects is exerting a gravitational force on the floating tool? the Earth, the Moon, the astronaut, the S
    10·2 answers
  • Un hombre de pie puede ejercer la misma fuerza con sus piernas tanto en la tierra como en la luna. Sabemos que la masa del hombr
    10·1 answer
  • How are you progressing towards the goals you set for yourself? What do you need to keep on track?
    12·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!