4.) A boat heading north crosses a wide river at a velocity of 2.778 m/s. The river current pushes the boat east at a constant velocity of 1.389 m/s. Find the resultant velocity. a.) 3.11 m/s b.) 9.65 m/s c.) 0.78 m/s d.) 6.38 m/s
Answer:
Resultant velocity = 3.11 m/s.
Explanation:
It is given that,
The velocity of a boat is 2.778 m/s due North
The velocuity of river is 1.389 m/s due east.
We need to find the resultant velocity. The angle between these two velocities is 90 degrees. The resultant is given by :
[tex]v=\sqrt{v_b^2+v_r^2} \\\\v=\sqrt{2.778 ^2+1.389 ^2} \\\\v=3.11\ m/s[/tex]
So, the correct option is (a).
A rotating pulley completes 12 rev in 4 secs determine the average angular velocity in rev /s, rpm and in rad/s
Answer: The average angular velocity for a rotating pulley is 3 rev/s, 180 rpm, 6π rad/s.
The pulley turns rotating when the rope tugged and completes 12 rev in 4 seconds.
How to determine the average angular velocity?If we consider a pulley rotating in a same axis, every point in the pulley has the same angular velocity.
Formula for angular velocity:
ω = Δθ / Δt
The average angular velocity can be defined as the ratio of the angular displacement to the time.
θ = 12 rev, t = 4s
1 revolution = 2π rad
It can be solved as:
Revolutions / second:
rev / s = 12 / 4
= 3
Revolutions per minute:
rpm = ( 12/4) × 60
= 180
Radian / second :
rad/s = (12×2π / 4 )
= 6π
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binary ionic compounds are called salts. true or false
Answer:
True
Explanation:
APEX APPROVED
12. Describe Binding energy and how it plays a role in nuclear fusion up to 56Fe (the synthesis of iron
nuclei). Include a description of the relationship between the strong nuclear force, the
electromagnetic force, and the number of nucleons involved in the fusion in your answer.
Help me on thiss one once again ughh ! asap ! hurry
A car accelerates from 1.5 to 18 m/sec in 9.6 seconds. Calculate its acceleration. and the other one is During a race, you speed up from 2.2 m/sec to 4 m/sec in 3.2 seconds. (a) What is your change in speed? ____ m/sec (b) What is your acceleration? ___ m/sec2
Answer:
(1) The acceleration is 1.72 m/s²
(2) (a) The change in speed is 1.8 m/s
(2) (b) The acceleration is 0.563 m/s²
Explanation:
(1)
Given;
initial velocity, u = 1.5 m/s
final velocity, v = 18 m/s
time of motion, t = 9.6 s
The acceleration is given by;
a = (v - u) / t
a = (18 - 1.5) / 9.6
a = 1.72 m/s²
(2)
Given;
initial speed, u = 2.2 m/s
final speed, v = 4 m/s
time of motion, t = 3.2 s
(a) The change in speed is given by;
Δv = v - u
Δv = 4 m/s - 2.2 m/s
Δv = 1.8 m/s
(b) the acceleration is given by;
a = Δv / t
a = 1.8 / 3.2
a = 0.563 m/s²
IDK MORE POINTS BUT SAY SOMTHING FUNNY
Not the place for this but yesterday I ate a clock, it was very time consuming.
What is brown and sticky
A STICK GET YOUR MIND OUT OF THE GUTTER
Which of the following would be best for absorbing light?
a A mirror
b A black shirt
c glass
d concrete
Which is a factor that keeps Earth in orbit around the sun
Answer:
Gravity
Explanation:
Newton contributions
Challenge: Write a Poem
Answer:
okkk soo...
Friendship is one of life's greatest treasures. Friends that are loyal are always there to make you laugh when you are down, they are not afraid to help you avoid mistakes and they look out for your best interest. This kind of friend can be hard to find, but they offer a friendship that will last a lifetime. Other friends may not be quite as loving. The pain caused by a friendship marred by betrayal is not easy to overcome. In fact, many poems find their inspiration from the joy brought about by a loving friendship or the pain caused by a failed friendship.
Explanation:
Branden ran at 6 m/s for a time of 300s. How much distance did he cover during his run?
Answer:
The covered distance was 1800 [m]
Explanation:
In order to solve this problem we must use the following formula of kinematics. It is important to make it clear that Branden's speed never changes during that time, or therefore the speed is constant.
[tex]x = x_{o}+v*t\\[/tex]
where:
x = distance [m]
Xo = initial position = 0
v = velocity = 6 [m/s]
t = 300 [s]
Now replacing we have:
x = 0 + (6*300)
x = 1800 [m]
Plz I need help on my last question
Answer:
Dispalcement(s)=v*t
=8.1*6
=48.6m
Fill in the blanks to complete the statements.
A paper plane moving through the air experiences air _____ .
Frictional forces acting on an object are often converted into ______
energy, which causes the temperature of the object to rise slightly.
Answer:
Resistance and thermal
Explanation:
Edge 2020
A paper plane moving through the air experiences air resistance.
Frictional forces acting on an object are often converted into thermal energy, which causes the temperature of the object to rise slightly.
What is Frictional forces?Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other.
What is thermal energy?Thermal energy refers to the energy contained within a system that is responsible for its temperature. Heat is the flow of thermal energy.
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lily took 57 seconds to walk from schoolroom to library. if the distance between the classroom and library was 38m, at what average speed did lily walk in m/min?
Answer:
7mph
Explanation:
Which model of the atom has electrons traveling in specific paths around the nucleus? Bohr's model Rutherford's model Thomson's model Dalton's model
Answer:
A, Bohr's model
Explanation:
Took the quiz, hope it's right for you.
(The other three did have something to do with it they just didn't create that specific model)
The model of the atom that has electrons traveling in specific paths around the nucleus is Rutherford's model.
Therefore, the correct answer is option B
J. J Thomson proposed that the atom is a sphere of positively charged matter in which negatively charged electron are embedded.
In Rutherford's model of atomic structure, the electrons moves in orbits by electrostatic attraction to the positively charged nucleus.
According to Dalton's atomic theory, atom were indestructible and indivisible solid particle.
Bohr's model made assumption that electron can only exist in circular orbits of definite quantum energy.
According to the question, the model of the atom that has electrons traveling in specific paths around the nucleus is Rutherford's model.
Therefore, the correct answer is option B
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PLEASE HELP ME
A boulder is raised above the ground so that the gravitational potential energy relative to the ground is 310 J. Then it is dropped. What is its kinetic energy just before it hits the ground?
Answer:
try this
Explanation:
The energy of a falling object when it hits the ground is equaled to the energy it starts with because the potential energy is converted into kinetic energy entirely with the height at 0. This means the energy would be 200 J.
RESULT
awnser thiss i need awnsers
Answer:
B
Explanation:
Density = mass / volume
Less dense objects float to the surface so if the liquid becomes 1000 kg/m3 then it is the densest thing in the mixture, except for Q which has a density = to that of the water so it will stay in place around the middle, since the other two are more dense they will go to the bottom of the container.
can energy change in physical change
what does the galaxy made of ?
When you sit in a chair, your body exerts a downward force on the chair. What
is the reaction force?
A. The floor pushes up on the chair.
B. The chair pushes down on the floor.
C. Earth's gravity pulls up on the chain
D. The chair pushes up on your body.
Answer:
ITS D !!!
Explanation:
IN ME WE TRUST
When you sit on the chair, your body will exert a downward force and in reaction, the chair pushes up on your body. Hence, option D is correct.
What is a Reaction Force?A building experiences a reaction force when it rests against another object. Calculating the reaction forces at the supports as a result of the forces operating on the beam is a necessary step in the analysis of a beam structure. The reaction forces can be calculated using a free body diagram of the entire beam.
Corrosion can be caused by reaction forces. For instance, due to the system's increased stiffness, reaction forces increase when bearing clearances are reduced from 350 mm to 150 mm.
According to the question, when the body will exert a downward force that is mg due to gravity, the chair will make a normal reaction force which will be equal to the force applied by the body on the chair.
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HELP RN PLEASSEEE!!! HELP!!
Choose all the answers that apply.
According to Newton's second law of motion:
1.objects at rest will remain at rest unless acted upon by an outside force
2.mass has an inverse relationship with acceleration
3.the greater the magnitude of force, the faster the acceleration
4.acceleration is caused by unbalanced forces
5.every action has an equal and opposite reaction
4. Hijackers are taking over a plane, They tell the pilot to get to Spain as fast as possible. The plane goes from 900
km/hr (beginning speed) to 1140 km/hr (final speed) in just 6 seconds. What is the acceleration of the plane?
List two objects here on Earth that are sources of radiant energy. How can you tell they emit radiant energy?
A Parachutist with a camera, with descending at a speed of 12.5m/s, releases, the camera at an altitude of 64.3m. What is the magnitude of the velocity of the camera just before it hits the ground ? The acceleration of gravity is 9.8 m/s and air friction is negligible. How long does it take the camera to reach the ground
Given :
Initial velocity, u = 12.5 m/s.
Height of camera, h = 64.3 m.
Acceleration due to gravity, g = 9.8 m/s².
To Find :
How long does it take the camera to reach the ground.
Solution :
By equation of motion :
[tex]h = ut+\dfrac{gt^2}{2}[/tex]
Putting all given values, we get :
[tex]12.5t+\dfrac{9.8t^2}{2}=64.3\\\\4.9t^2+12.5t=64.3[/tex]
t = 2.56 and t = −5.116.
Since, time cannot be negative.
t = 2.56 s.
Therefore, time taken is 2.56 s.
Hence, this is the required solution.
Please help ASAP WILL GIVE BRAINLIEST
why is it important to use the correct number of significant digits when reporting the results of an experiment
A. So other scientist can see how spread out your data are
B. So other scientists can see how many separate trials you preformed
C. So other scientists can compare their experimental results with yours
D. So other scientistcan see how precise your measurements were
Answer:
D
Explanation: It makes the most sense. Plz mark brainliest
Answer:
D
Explanation:
So other scientist can see how precise your measurements are
To get employees to work longer hours, employers often offer __________ in the form of extra pay.
A.
costs
B.
benefits
C.
incentives
D.
consequences
Answer:
C
Explanation:
I took the test
A scientist who conducted an experiment obtained an unexpected result. What will she most likely do with the unexpected result? leave it out of her analysis and final report stop the experiment and begin again change the procedures and try again develop a new question to be investigated
Answer: stop the experinment and begin again sometimes the result of the experiment may give you unexpected results due to the fact that you may have missed a certain step or you didn't follow the procedure accurately to the dot, hence it's important to redo the experiment and see if every step was followed accurately before you can discard the results or change the procedure.
Explanation:
Answer:
d
Explanation:
If an object is moving up, is it considered to have a positive or negative velocity?
Answer:
A positive velocity
Explanation:
Which one of the following is not a fundamental physical quantity??! A. Temperature b. Current c. Area d. Mass
Answer:
Out of this, Area is not a fundamental physical quantity.
A car starts from rest and accelerates uniformly over a time of 7.31 seconds for a distance of 160 m. Determine the acceleration of the car.
Answer:
Since it is given that car starts from rest so initial velocity
u
=
0 m/s
. The position of car is given, so
S
=
215 m
.
Explanation:
6346345
Answer:
215 m
Explanation:
You walk east for 30 m, then decide to walk north foranother 30 m. What is the angle of direction of your displacement?
Answer:
Displacement is 42.426 m NE and the angle is opposite/adjacent or 30/30 which would equal 1 degree which doesn't seem right but hopefully its an answer.
Explanation: