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
Ivahew [28]
3 years ago
14

After t hours a freight train is s(t) = 18t2 − 2t3 miles due north of its starting point (for 0 ≤ t ≤ 9). (a) Find its velocity

at time t = 3 hours. 108 Incorrect: Your answer is incorrect. mi/hr (b) Find its velocity at time t = 7 hours. 546 Incorrect: Your answer is incorrect. mi/hr (c) Find its acceleration at time t = 1 hour. 42 Incorrect: Your answer is incorrect. mi/hr2
Physics
1 answer:
BartSMP [9]3 years ago
4 0

Answer:

Explanation:

Given the equation modelled by the height of the train given as:

s(t) = 18t²-2t³ for for 0 ≤ t ≤ 9

a) Velocity is the rate of change of displacement.

Velocity = dS(t)/dt

V = dS(t)/dt = 36t - 6t² miles

Velocity at t = 3hrs is determiner by substituting t = 3 into the velocity function.

V = 36(3) -6(3)²

V= 108 - 72

Velocity = 36mi/hr

b) for Velocity at time = 7hrs

V(7) = 36(7) - 6(7)²

V(7) = 252 - 294

V(7) = -42mi/hr

The velocity at t = 7hrs is -42mi/hr

c) Acceleration is the rate of change of velocity.

a(t) = dV(t)/dt

Given v(t) = 36t - 6t²

a(t) = 36 - 12t

Acceleration at t=1 is given as:

a(1) = 36 -12(1)

a(1) = 24mi/hr²

You might be interested in
I really need Brainliest i am desprate
kondor19780726 [428]

Hy tikki! I've asked some questions, so of you find the questions as easy, then answer it. I'll surely mark you as brainliest :)

6 0
3 years ago
An action potential arriving at the presynaptic terminal causes what to occur?
Ulleksa [173]

Answer:

Voltage-gated calcium ion channels open, and calcium ions diffuse into the cell

5 0
3 years ago
How much work must be done to bring three electrons from a great distance apart to 3.0×10−10 m from one another (at the corners
Natasha_Volkova [10]

Answer:

Potential\ Energy=Work \ Done=2.301*10^{-18} J

Work  done to bring three electrons from a great distance apart to 3.0×10−10 m from one another (at the corners of an equilateral triangle) is 2.301*10^{-18} Joules

Explanation:

The potential energy is given by:

U=Q*V

where:

Q is the charge

V is the potential difference

Potential Difference=V=\frac{kq}{r}

So,

Potential\ Energy=\frac{Qkq}{r} \\Q=q\\Potential\ Energy=\frac{kq^2}{r}

Where:

k is Coulomb Constant=8.99*10^9 Nm^2/C^2

q is the charge on electron=-1.6*10^-19 C

r is the distance=3.0*10^{-10}m

For 3 Electrons Potential Energy or work Done is:

Potential\ Energy=3*\frac{kq^2}{r}

Potential\ Energy=3*\frac{(8.99*10^9)(-1.6*10^{-19})^2}{3*10^{-10}}\\Potential\ Energy=2.301*10^{-18} J

Work  done to bring three electrons from a great distance apart to 3.0×10−10 m from one another (at the corners of an equilateral triangle) is 2.301*10^{-18} Joules

7 0
3 years ago
A frog jumps for 4.0 seconds at a maximum horizontal distance of 0.8m. what is its velocity along the road?
Lerok [7]

Answer:

The frog's horizontal velocity is 0.2 m/s.

Explanation:

To solve this problem, we must first remember what velocity is and how we solve for it.  Velocity can be solved for using the formula x/t, where x represents horizontal distance and t represents time (in seconds), that it takes to travel this distance.  If we plug in the given numbers for these variables and solve, we get the following:

v = x/t

v = 0.8m/4s

v = 0.2 m/s

Therefore, the correct answer is 0.2 m/s.  We can verify that these units are correct because the formula calls for distance divided by time, so meters per second is a sensible answer.

Hope this helps!

3 0
3 years ago
Use the Venn Diagram to compare and contrast solar and lunar eclipses.
Sergio [31]
From our perspective on Earth, two types of eclipses <span>occur: </span>lunar<span>, the blocking of the </span>Moon<span> by Earth's shadow, and </span>solar, the obstruction of the Sun by the Moon<span>. ... When Earth passes directly </span>between<span> Sun and </span>Moon<span>, its shadow creates a </span>lunar eclipse<span>.</span>
5 0
3 years ago
Other questions:
  • One horsepower (1 hp) is the unit of power based on the work that a horse can do in one second. This is defined, in English unit
    12·1 answer
  • 1. A 700kg racecar slowed from 30m/s to 15 m/s. What was its change in Momentum? 2. If the car in the above problem took 5 secon
    14·1 answer
  • Hi! Can you help me? :) A satellite's speed is 10,000 m/s. After 1 min, it is 5,000 m/s. What is the satellite's acceleration? T
    11·2 answers
  • The concentration of an isotope is 1/500 of its initial value after one day. What is the rate of decay?
    5·1 answer
  • which has a greater speed a heron hat travels 600m in 60 seconds or a duck that travels 60 m in 5 seconds? Explain
    6·2 answers
  • A skateboarder shoots off a ramp with a velocity of 5.1 m/s, directed at an angle of 55° above the horizontal. The end of the ra
    7·1 answer
  • 3. What conclusion would you draw if a seismogram from a particular seismic station showed only P waves?
    10·1 answer
  • Which of the following occurs when the fight-or-flight response is triggered?
    6·1 answer
  • a car advertisement States that a certain car can accelerate from rest to70km/h in 7seconds find the car's average acceleration​
    15·1 answer
  • QUICK HELP ILL MARK U BRAINLIEST
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!