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
RoseWind [281]
3 years ago
5

Danny is riding his bike at 12m/s he tries to pop a wheelie but he fails hits a curb flies through the air and comes to a comple

te stop in 30 seconds what is Danny's deceleration
Physics
1 answer:
maxonik [38]3 years ago
8 0

Answer:

a = -0.4m/s²

Explanation:

v_f = v_I + (a)(t)

a(t) = v_f-v_I

a = (v_f-v_I)/t

a = (0m/s-12m/s)/30s

a = -0.4m/s²

You might be interested in
In 1 to 2 sentences explain how you would determine the constant K for a spring
Olin [163]

When spring times comes around you ever be like, "k." If you feel like that every year during spring then there you go

8 0
3 years ago
friction force is the opposition to the motion of surfaces sliding across each other. what is one factor that affects the amount
ruslelena [56]

Answer

Nature of the surfaces.


Explanation

Friction is the the force that opposes motion between two surfaces that are in relative motion. If two objects are in contact, one of it or both must be in motion for friction to exist.

Friction is affected by a number of factors.

One is the weight of the object. The more the weight of the object the higher the friction between it and the surface.

The other factor is the nature of the surfaces. Rough surfaces contribute to high friction while smooth surfaces reduces the friction between surfaces.  

3 0
3 years ago
The concentration of Biochemical Oxygen Demand (BOD) in a river just downstream of a wastewater treatment plant’s effluent pipe
shtirl [24]

Answer:

The BOD concentration 50 km downstream when the velocity of the river is 15 km/day is 63.5 mg/L

Explanation:

Let the initial concentration of the BOD = C₀

Concentration of BOD at any time or point = C

dC/dt = - KC

∫ dC/C = -k ∫ dt

Integrating the left hand side from C₀ to C and the right hand side from 0 to t

In (C/C₀) = -kt + b (b = constant of integration)

At t = 0, C = C₀

In 1 = 0 + b

b = 0

In (C/C₀) = - kt

(C/C₀) = e⁻ᵏᵗ

C = C₀ e⁻ᵏᵗ

C₀ = 75 mg/L

k = 0.05 /day

C = 75 e⁻⁰•⁰⁵ᵗ

So, we need the BOD concentration 50 km downstream when the velocity of the river is 15 km/day

We calculate how many days it takes the river to reach 50 km downstream

Velocity = (displacement/time)

15 = 50/t

t = 50/15 = 3.3333 days

So, we need the C that corresponds to t = 3.3333 days

C = 75 e⁻⁰•⁰⁵ᵗ

0.05 t = 0.05 × 3.333 = 0.167

C = 75 e⁻⁰•¹⁶⁷

C = 63.5 mg/L

5 0
3 years ago
Unless indicated otherwise, assume the speed of sound in air to be v = 344 m/s. You have a stopped pipe of adjustable length clo
faltersainse [42]

Answer:

Length of pipe = 0.057 meter

Explanation:

Speed of a transverse wave on a string

v = \sqrt{\frac{F}{\mu} }

where F is the tension in string and \mu is the mass per unit length

Thus,

\mu = \frac{m}{L}

Substituting the given values we get -

\mu = \frac{7.25 * 10^{-3}}{0.62}\\mu = 0.0117 \frac{Kg}{m}

Speed of a transverse wave on a string

v = \sqrt{\frac{4510}{0.0117} } \\v = 620.86 \frac{m}{s}

For third harmonic wave , frequency is equal to

f = \frac{nv}{2L}

Substituting the given values, we get -

f = \frac{3 * 620.86}{2 * 0.62} \\f = 1502.08

Length of pipe

L = \frac{nv}{4 f}

Substituting the given values we get

n = 1 for first harmonic wave

L = \frac{344* 1}{4*1502.08} \\L = 0.057

Length of pipe = 0.057 meter

5 0
3 years ago
The speed of the proton when it reaches point
romanna [79]
1) An electron is moving east in a uniform electric field of 1.53N/C directed to the west. At point A, the velocity of the electron is 4.51�105m/s pointed toward the east. What is the speed of the electron when it reaches point B, which is a distance of 0.400m east of point A? 2) A proton is moving in the uniform electric field of part A. At point A, the velocity
8 0
3 years ago
Other questions:
  • How strongly the planet you're on Pulls on you
    6·2 answers
  • Which statement is true?
    9·1 answer
  • Why does the hood of a car heat up after the car has been running for a while? A) According to the fourth law of thermodynamics,
    11·2 answers
  • A typical reaction time to get your foot on the brake in your car is 0.2 second. If you are traveling at a speed of 60 mph (88 f
    8·2 answers
  • During her first trip abroad, Paula was surprised to find that people in other cultures ate such foods as snails, squid, insects
    5·1 answer
  • If you wanted to detect x rays coming from the sun, where would you place the detector? Why?
    5·2 answers
  • uppose that the terminal speed of a particular sky diver is 150 km/h in the spread-eagle position and 320 km/h in the nosedive p
    5·1 answer
  • A sample contains 20 kg of radioactive material. The decay constant of the material is 0.179 per second. If the amount of time t
    13·1 answer
  • What is equilibrium state​
    15·2 answers
  • What are the limitations of using solar panels?​
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!