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
Andreyy89
2 years ago
10

Suppose that a person gets hit by a bus moving at 30 mi/h with a 58,000 lbs of force in the direction of motion. If the mass of

the bus is 40,000 lbs and persons is 150 lbs and if the impact lasts only 0.007 seconds.
A. Determine the speed of the person at the end of the impact and convert to mi/h.

B. What is the expected speed of the person at the end of the impact and does your finding agree with that expectation?
Physics
1 answer:
alexandr402 [8]2 years ago
3 0

The impulse of a force is due to the change in the motion of an object

A. The persons speed after impact is approximately 59.38 mi/h

B. The expected speed is <u>29.89 mi/h</u> which is less than the findings

Reason:

Known parameters are;

The speed of the bus, v = 30 mi/h

The force with which the person was hit, F = 58,000 lbs

Mass of the bus, M = 40,000 lbs

Mass of the person, m = 150 lbs

Duration of the impact, Δt = 0.007 seconds

A. The speed of the person at the end of the impact, <em>v</em>, is given as follows;

The impulse of the force = F × Δt = m × Δv

For the person, we get;

58,000 lbf ≈ 1866094.816 lb·ft./s²

58,000 lbf × 0.007 s = 150 lbs × Δv

1,866,094.816 lb·ft./s²

\Delta v = \dfrac{1,866,094.816\ lbs \times 0.007 \, s}{150 \, lbs} \approx  87.084  \ ft./s

Δv = v₂ - v₁

The initial speed of the person at the instant, can be as v₁ = 0

The final speed, v₂ = Δv - v₁

∴ v₂ ≈  87.084 ft./s - 0 = 87.084 ft./s

≈ <u>87.084 ft./s</u>

<u />v_2 \approx \dfrac{87.084 \ ft./s}{y} \times\dfrac{1 \ mi}{5280 \ ft.} \times \dfrac{3,600 \ s}{1 \, hour} \approx 59.38 \ mi/h<u />

The speed of the person at the end of the impact, v₂ ≈ <u>59.38 mi/h</u>

B. Where the momentum is conserved, we have;

m₁·v₁ + m₂v₂ = (m₁ + m₂)·v

v = \dfrac{m_1 \cdot v_1 + m_2 \cdot v_2}{m_2 + m_1}

v = \dfrac{40,000 \times 30  + 150 \times 0}{40,000 + 150} \approx 29.89

The expected speed of the person at the end of the impact is 29.89 mi/h, and therefore, <u>the findings does not agree with the expectation</u>

Learn more here:

brainly.com/question/18326789

You might be interested in
Des Linden won the Boston marathon in 2018, becoming the first American woman to win since 1985. The harsh conditions (heavy rai
ankoles [38]

Answer:

3050.6 Litre .

Explanation:

Total time of heart beat = Total time of race  = 2 hrs , 39 minutes and 54 seconds

= 2 x 60 + 39 + 54/60 min

= 120 + 39 + .9 min

= 159.9 min

rate of heart beat = 170 per min

Total no of heart beat during race = 170 x 159.9

volume of blood per kg per beat = 2.5 mL per kg of weight

body weight  = 99 pounds = .4535 x 99  kg = 44.89 kg

volume of blood  per beat = 2.5 mL x 44.89 mL

= 112.225 mL .

Total required volume of blood =  112.225  x 170 x 159.9 mL

= 3050612 mL

= 3050.6 L.

6 0
2 years ago
What is the gravitational potential energy of a 5 kg box if it is lifted 3 m from the floor?
Murrr4er [49]

Answer:

Its gravitational potential energy is 117.6 joules.

Explanation:

5 0
2 years ago
An athlete is working out in the weight room. he steadily holds 50 kg above his head for ten seconds which statement is true abo
Andrews [41]
Hi. The answer to your question is the first option.

The athlete isn’t doing any work because he doesn’t move the weight.

Hope this helps :))
5 0
3 years ago
Sort the length measurements in increasing order of magnitude from smallest to largest Drag each tile to the correct box Tiles S
wariber [46]

Answer:

Nanometer, micrometer, centimeter, decimeter, dekameter, kilometer

Explanation:

Given the following length measurement :

micrometer Kilometer decimeter centimeter nanometer dekameter.

Sorting in increasing order of magnitude from Smallest to Largest.

Expressing in terms of meters :

1 meter = 0.1 decameter

1 meter = 1 × 10^9 nanometer

1 meter = 1 × 10^2 centimeter

1 meter = 1 × 10^1 decimeter

1 meter = 0.001 kilometer

1 meter = 1 × 10^6 micrometers

Hence, arranging from Smallest to Largest :

Nanometer, micrometer, centimeter, decimeter, dekameter, kilometer

3 0
3 years ago
Someone help me with this PE question?
katovenus [111]

Answer:

Your abdominals

Explanation:

3 0
2 years ago
Read 2 more answers
Other questions:
  • A motorist inflates the tires of her car to a pressure of 180 kPa on a day when the temperature is -8.0° C. When she arrives at
    9·1 answer
  • What determines the length of a year for a planet
    7·2 answers
  • The coefficient of cubical expansion of a substance depends upon
    9·1 answer
  • Studies have shown that driving after drug use was more common among drivers who were
    8·1 answer
  • An ideal solenoid having a coil density of 5000 turns per meter is 10 cm long and carries a current of 4.0
    11·1 answer
  • Convert 6.95×105 cal to joules. recall that 1 cal=duncan takes a break from studying and goes to the gym to swim laps. if swimmi
    7·1 answer
  • What characteristic makes Biology a science, but not Art History?
    15·2 answers
  • (1 point) A horizontal clothesline is tied between 2 poles, 20 meters apart. When a mass of 5 kilograms is tied to the middle of
    15·1 answer
  • Which warning sign suggests being bullied?
    11·1 answer
  • You will be colliding two carts in this lab. Select all the systems for which you predict the total momentum of the system will
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!