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
Licemer1 [7]
3 years ago
8

A train rolls past a stationary observer. To him, the train is moving at a speed of 23m/s west, and a woman on the train is movi

ng at a speed of 22.4m/s west. How long does it take the women to move 13 m relative to the train?
A. 24.1s
B.21.7s
C. 23.2s
D. 25.6s
Physics
1 answer:
GREYUIT [131]3 years ago
4 0

Answer:

21.7 seconds.

Explanation:

Woman's velocity relative to train (23 m/s - 22.4 m/s) = 0.6 m/s

Distance woman wants to travel = 13m

To find how long she will take to move 13m relative to the train, take the distance she wants to travel divided by her velocity relative to the train.

(13m)/(0.6 m/s) = 21.6667 seconds or 21.7 seconds.  

Therefore, it will take the woman 21.7 seconds to move 13m.

You might be interested in
A wind turbine is an example of what kind of device
Liula [17]

Answer:

it’s an example of a generator.

Explanation:

3 0
2 years ago
An object is moving along a straight line, and the uncertainty in its position is 1.90 m.
just olya [345]

Answer:

2.78\times 10^{-35}\ \text{kg m/s}

6.178\times 10^{-34}\ \text{m/s}

0.31\times 10^{-4}\ \text{m/s}

Explanation:

\Delta x = Uncertainty in position = 1.9 m

\Delta p = Uncertainty in momentum

h = Planck's constant = 6.626\times 10^{-34}\ \text{Js}

m = Mass of object

From Heisenberg's uncertainty principle we know

\Delta x\Delta p\geq \dfrac{h}{4\pi}\\\Rightarrow \Delta p\geq \dfrac{h}{4\pi\Delta x}\\\Rightarrow \Delta p\geq \dfrac{6.626\times 10^{-34}}{4\pi\times 1.9}\\\Rightarrow \Delta p\geq 2.78\times 10^{-35}\ \text{kg m/s}

The minimum uncertainty in the momentum of the object is 2.78\times 10^{-35}\ \text{kg m/s}

Golf ball minimum uncertainty in the momentum of the object

m=0.045\ \text{kg}

Uncertainty in velocity is given by

\Delta p\geq m\Delta v\geq 2.78\times 10^{-35}\\\Rightarrow \Delta v\geq \dfrac{2.78\times 10^{-35}}{m}\\\Rightarrow \Delta v\geq \dfrac{2.78\times 10^{-35}}{0.045}\\\Rightarrow \Delta v\geq 6.178\times 10^{-34}\ \text{m/s}

The minimum uncertainty in the object's velocity is 6.178\times 10^{-34}\ \text{m/s}

Electron

m=9.11\times 10^{-31}\ \text{kg}

\Delta v\geq \dfrac{\Delta p}{m}\\\Rightarrow \Delta v\geq \dfrac{2.78\times 10^{-35}}{9.11\times 10^{-31}}\\\Rightarrow \Delta v\geq 0.31\times 10^{-4}\ \text{m/s}

The minimum uncertainty in the object's velocity is 0.31\times 10^{-4}\ \text{m/s}.

6 0
2 years ago
A student drops a ball from the top of a tall building; it takes 2.9 s for the ball to reach the ground.
AlexFokin [52]

<h2><u>We have</u>,</h2>

  • Initial velocity (u) = 0 m/s
  • Time taken (t) = 2.9s
  • Acceleration due to gravity (g) = + 10 m/s² [Down]

<h2><u>To calculate</u>,</h2>

  • Final velocity (v)
  • Height (h)

<h2><u>Solution</u><u>,</u></h2>

→ v = u + gt

→ v = 0 + 10(2.9)

→ v = 29 m/s \qquad … ( Ans )

And,

→ h = ut + ½gt²

→ h = 0(2.9) + ½ × 10 × (2.9)²

→ h = 5 × 8.41

→ h = 42.05 m \qquad … ( Ans )

4 0
2 years ago
A 125kg bumper car going 18.5 m/a bumps a 187.kkg bumper car at rest. if the first car (125kg) bounces back at 8 m/s what is the
kozerog [31]
  <span><span>Imagine we have a 2 lb ball of putty moving with a speed of 5 mph striking and sticking to a 18 lb bowling ball at rest; the time it takes to collide is 0.1 s. After the collision, the two move together with a speed of v1. To find v1, use momentum conservation: 2x5=(18+2)v1, v1=0.5 mph. </span><span>Next, imagine we have a 18 lb bowling ball moving with a speed of 5 mph striking and sticking to a 2 lb ball of putty at rest; the time it takes to collide is 0.1 s. After the collision, the two move together with a speed of v2. To find v2, use momentum conservation: 18x5=(18+2)v2, v2=4.5 mph. </span><span>
</span><span>
</span><span>now figure out your problem its really easy let me know if you need more help  </span></span>
3 0
3 years ago
The gravitational self potential energy of a solid ball of mass density ρ and radius R is E. What is the gravitational self pote
Alenkasestr [34]
It will be
E = mgh.
where h and g are constant thus
m can be written as 4/3πr^3*density
E = 4/3πr^3* density
E? = 4/3π(2R)^3* density
= 4/3π8r^3
thus the e will be 4/3π8r^3* density/4/3πr^3*density nd thus you get 8E ..
8 0
3 years ago
Other questions:
  • What's the difference between here and there?
    7·2 answers
  • Two tuning forks are played at the same time. One has a frequency of 176 Hz and the other is 178 Hz. How many beats per second a
    7·1 answer
  • Help please suffering
    5·1 answer
  • 2) A constant net force acts on an object. Describe the motion of the object.?
    14·1 answer
  • A quantity of gas is contained in a sealed container of fixed volume. The temperature of the
    5·1 answer
  • 4. Three methods that people use are:
    11·1 answer
  • A ball of mass 2 kg is being pulled sideways by a force 3 N to the right, and a force of 8N to the left - these are the only for
    10·1 answer
  • Is the force of gravity that attracts my body to the Earth related to the force of gravity between the planets and the Sun
    8·1 answer
  • The radius of our clock face is 9.2cm. It is 8:44; we are done at 9:11. How far will the minute hand (the larger one) travel?
    6·1 answer
  • The focal length of a diverging lens is negative. If f = −26 cm or a particular diverging lens, where will the image be formed o
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!