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
melomori [17]
3 years ago
15

Two roads intersect at right angles, one going north-south, the other east-west. an observer stands on the road 60 meters south

of the intersection and watches a cyclist travelling east at 10 meters per second. at what rate is the cyclist moving away from the observer 8 seconds after he passes through the intersection? (hint: remember 3-4-5 rightangled triangles.)

Physics
2 answers:
Sloan [31]3 years ago
7 0

observer is standing at distance d = 60 m south from the intersection

cyclist is travelling at speed v = 10 m/s

now after t = 8 s its displacement from intersection is given by

x = 10*8 = 80 m

so the position of cyclist makes an angle with the observer

\theta = tan^{-1}\frac{80}{60} = 53 degree

now the component of velocity of cyclist along the line joining its position with the observer is given as

v = v_o cos\phi

here

\phi = 90 -\theta

\phi = 90 - 53 = 37 degree

v = 10 cos37 = 8 m/s

so at this instant cyclist is moving away with speed 8 m/s

Anna007 [38]3 years ago
3 0

The cyclist moving away from the observer 8 seconds after he passes through the intersection at the rate 8 m/s

\texttt{ }

<h3>Further explanation</h3>

Vector is quantity that has magnitude and direction.

One example of a vector is displacement.

Let us now tackle the problem !

\texttt{ }

This problem is about Vector Diagram.

<u>Given:</u>

distance between observer and intersection = y = 60 m

speed of cyclist = v = 10 m/s

elapsed time = t = 8 s

<u>Asked:</u>

speed of cyclist relative to observer = v' = ?

<u>Solution:</u>

<em>Firstly , we will calculate the distance between the cyclist and intersection:</em>

x = v t

x = 10 \times 8

x = 80 \texttt{ m}

\texttt{ }

<em>Next , we could calculate the speed of cyclist relative to observer:</em>

v' = v \times \cos \theta

v' = v \times \frac{ x }{\sqrt{x ^2 + y^2}}

v' = 10 \times \frac { 80 }{\sqrt{80^2 + 60^2}}

v' = 10 \times \frac {4}{5}

v' = 8 \texttt{ m/s}

\texttt{ }

<h3>Conclusion :</h3>

The cyclist moving away from the observer 8 seconds after he passes through the intersection at the rate 8 m/s

\texttt{ }

<h3>Learn more</h3>
  • Direction of Displacement : https://brainly.ph/question/1746541
  • Scalar and Vector : https://brainly.ph/question/274572
  • Weight : https://brainly.ph/question/545327
  • Orientation of Vectors : https://brainly.ph/question/2121753

\texttt{ }

<h3>Answer details</h3>

Grade: High School

Subject: Physics

Chapter: Vectors

You might be interested in
A. Compare solids, liquids, and gases in terms of the way their volumes change (or don't change) when placed into different cont
svet-max [94.6K]

a) Solids keep shape, liquids take shape of containers but don't spill, gases take container's shape and spill out

b) if you heat gas, speed of its molecules will increase and they'll push the container's walls stronger, so the pressure will increase when the container heated

c) Heat flows from warmer to colder bodies

d) For monatomic gases it's U=1.5nRT only, molecular gas has bonds between atoms so total internal energy increases

e) Of gases

f) v=\sqrt{\frac{3RT}{M}}=321 m/s

g) U=5/2*nRT=37830.85 J

7 0
3 years ago
____________ are manufactured by the brain to help relieve pain. Ventricles Epinephrines Endorphins Phalanges
VMariaS [17]

It's Endorphins. That's a pain killer produced by the brain.

5 0
3 years ago
Read 2 more answers
Design a solution that can monitor and minimize the melting of sea ice caused by human activity
dedylja [7]

Answer:

CO2 emissions from fossil fuel burning should be minimized at all cost. The CO2 are gotten when the carbons from hydrocarbons react with air(oxygen). This gas erodes the ozone layer which makes the melting of ice caps faster due to increased amount of heat radiations on the earth. This is the only best and permanent solution to the reduction of the amount of heat rays on the earth which is a global problem.

Objects which reflects back the sunrays could also be inserted into the sea to prevent the melting of the ice caps.

7 0
3 years ago
You are driving your motorcycle in a circle of radius 75 m on wet pavement. what is the fastest you can go before you lose tract
stira [4]

On driving your motorcycle in a circle of radius 75 m on wet pavement, the fastest you can go before you lose traction, assuming the coefficient of static friction is 0.20 is 147m/s

Friction helps to maintain the slipping of the vehicle on the road hence lays a very important role.

Maximum velocity of a road with friction is given by the formula,

v = μRg

where, v is the maximum velocity

μ is the coefficient of static friction

R is the radius of the circle road

g is the acceleration due to gravity

Given,

μ = 0.20

R = 75m

g = 9.8m/s²

On substituting the given values in the above formula,

v = 0.20× 75 ×9.8

v = 147m/s

So, the Maximum velocity of the wet road is 147m/s.

Learn more about Velocity here, brainly.com/question/18084516

#SPJ4

3 0
2 years ago
What is the example of current electricity?
Nikitich [7]
Flow of electrons through a copper wire
8 0
3 years ago
Other questions:
  • A car collides into a concrete wall going 25.0 m/s . It stops in 0.141 seconds and has a change in momentum of 39,400. What is t
    8·1 answer
  • Which of the following is NOT NECESSARILY a property of an air mass?
    12·1 answer
  • The image above shows a block pulled across a table. The spring scale which measures in Newtons, reads the force resisting the m
    5·1 answer
  • If a spring stores 5 J of energy when it's compressed by .5 m, what is the spring constant of the spring?
    11·2 answers
  • If the density of a diamond is 3.5 g/cm", what would be the mass of a diamond whose
    11·1 answer
  • Select all that apply.
    5·1 answer
  • What is the tension in the cord after the system is released from rest? Both masses (A and B) are 10-kg.
    9·1 answer
  • A 0.0400-g positive charged ball with charge q = 6.40 μC is resting on a flat, frictionless horizontal surface. For a time of t
    15·1 answer
  • Phyllis is calculating the path of a space probe that will travel to Pluto. On the way to Pluto, the probe will pass Mars, Satur
    7·2 answers
  • Impulse: A batter applies an average force of 8000 N to a baseball for 1.1 ms. What is the magnitude of the impulse delivered to
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!