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
suter [353]
3 years ago
5

A river 800m wide flows at the rate of 5km/h . A swimmer who can swim at 10km/h in still water wants to cross the river straight

.
Along what direction must he strike ?

Please solution with explanation
Physics
1 answer:
LuckyWell [14K]3 years ago
6 0

Answer:

At an angle of 30^{\circ}

Explanation:

Assume the river flows from East to West so for the swimmer to cross across it, assume he crosses it from West to East.

The resultant speed will be given by

R= \sqrt {10^{2}-5^{2}=\sqrt {75}\approx 8.66 km/h\\Direction=sin^{-1}\frac {5}{10}\approx 30^{\circ}

You might be interested in
A wheel has a radius of r = 2.0 m and it rolls down a smooth incline. The height of the incline is h = 8.0 m . What is the angul
zepelin [54]

The angular velocity of the wheel at the bottom of the incline is 4.429 rad/sec

The angular velocity (ω) of an object is the rate at which the object's angle position is changing in relation to time.

For a wheel attached to an incline angle, the angular velocity can be computed by considering the conservation of energy theorem.

As such the total kinetic energy (K.E) and rotational kinetic energy (R.K.E) at a point is equal to the total potential energy (P.E) at the other point.

i.e.

P.E = K.E + R.K.E

\mathbf{mgh = \dfrac{1}{2}m(r \times \omega)^2 + \dfrac{1}{2}\times I \times \omega^2}

\mathbf{gh = \dfrac{1}{2}(r \times \omega)^2 + \dfrac{1}{2}\times r^2 \times \omega^2}

\mathbf{2 \times \dfrac{gh}{r^2} =\omega^2 +  \omega^2}

\mathbf{2 \omega^2=2 \times \dfrac{9.81 \times 8 m }{2.0 ^2}  }

\mathbf{\omega^2=\dfrac{39.24 }{2}}

\mathbf{\omega=\sqrt{19.62 } \ rad/sec}

\mathbf{\omega=4.429 \ rad/sec}

Therefore, we can conclude that the angular velocity of the wheel at the bottom of the incline is 4.429 rad/sec

Learn more about angular velocity here:

brainly.com/question/1452612

4 0
2 years ago
Read 2 more answers
Which statement correctly compares sound and light waves?
vitfil [10]
Light travels as transverse waves and can go through the vacuum of space, while sound has longitude waves and needs to travel through something solid. It can’t travel through a vacuum of space like light.
3 0
3 years ago
Read 2 more answers
Can someone please help me with this
SashulF [63]
There’s no picture or question
3 0
3 years ago
Drag and drop the words into the correct locations to label the layers of the atmosphere, with the lowest layer at the bottom. (
professor190 [17]

Answer:

The top layer is exosphere. The fourth is the Thermosphere. The middle layer is the mesophere. The second layer is the Stratospere. the lowest layer is the troposphere

Explanation:

4 0
3 years ago
Read 2 more answers
A block of aluminium of density 7900 kg/m3 has a volume of 250 cm. Find the<br>mass of the block.​
pashok25 [27]

Answer:

mass of block=2.7 gm

Explanation:

concept: Density=mass/volume

given:ρ=2700 kg/m^3 and v=250 cm^3 (in cm^3 not in m^3)

=> v= convert cm^3 to m^3

there fore= 1 cm^3=1 cm*1 cm*1 cm

i.e 1 cm^3=1/100*1/00*1/100 m^3 => 1 cm^3=1/1000000 m^3

ρ=m/v

=>mass=ρ*volume

=>mass=2700*1/10^-6

=>mass=2.7*10^-3 kg =>2.7 gm

8 0
3 years ago
Other questions:
  • Explain how the meanings of the terms biotic factor and abiotic factor differ ?
    12·1 answer
  • What color will the paper appear? Explain why?
    15·1 answer
  • Stacy travels 5 times as fast as Eric. Traveling in opposite directions, they are 336 miles apart after 4 hours. Find their rate
    6·1 answer
  • What is the slope of a line that is perpendicular to the x-axis?
    14·1 answer
  • ______ are wind-created landforms in the western United States.
    5·2 answers
  • A 4.00 kg ball is moving at 4.00 m/s to the EAST and a 6.00 kg ball is moving at 3.00 m/s to the NORTH. The total momentum of th
    8·1 answer
  • If a force of 10 N acts on an object and an additional force of 6 N acts on the object in the same direction. What will be the n
    5·2 answers
  • What other issues, besides addiction, might go along with overuse of phones?
    9·1 answer
  • A) Khi nào một vật được coi là chuyển động ? Cho ví dụ ?
    5·1 answer
  • Determine the launch speed of a horizontally launched projectile that lands 26.3m from the base of a 19.3m high cliff
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!