Answer:
Electromagnetic spectrum is the arrangement of all kinds of radiation according to their frequency and wavelength. They don't require a material medium for their propagation.They are transverse waves that travel in a direction perpendicular to the direction of vibration.
a man can swim with a speed of 5m/s in calm water. if this man swims crosses a specific river his speed is 3m/s. if he takes the minimum time to cross the river find the speed of the flow of water in the river...
plz answer me with all the steps!
I'll give u points ..mark brainliest and follow u
Answer:
The speed of the flow of water in the river is 4 m/s.
Explanation:
Given that,
Speed of man = 5 m/s
If this man swims crosses a specific river his speed is 3 m/s.
If he takes the minimum time to cross the river
Let the speed of flow of water be [tex]v_{r}[/tex]
We need to calculate the speed of the flow of water in the river
Using formula for velocity
[tex]v_{rs}^2=v_{r}^2+v_{s}^2[/tex]
[tex]v_{r}^2=v_{rs}^2-v_{s}^2[/tex]
Where, [tex]v_{s}[/tex] = velocity of swimmer
[tex]v_{sr}[/tex] = relative velocity
[tex]v_{r}[/tex] = velocity of river
Put the value into the formula
[tex]v_{r}^2=5^2-3^2}[/tex]
[tex]v_{r}=\sqrt{5^2-3^2}[/tex]
[tex]v_{r}=4\ m/s[/tex]
Hence, The speed of the flow of water in the river is 4 m/s.
843 L - 0.028 kL = ______________L?
Answer: 815 L
Explanation:
0.028 kL=28L (times 1000)
843 L-0.0028 kL=843L-28L=815 L
Hope this helps!! :)
Please let me know if you have any question or need any further explanation
Effciency of a lever is never 100% or more. why?Give reason
Answer:
Ideally, the work output of a lever should match the work input. However, because of resistance, the output power is nearly always be less than the input power. As a result, the efficiency would go below [tex]100\%[/tex].
Explanation:
In an ideal lever, the size of the input and output are inversely proportional to the distances between these two forces and the fulcrum. Let [tex]D_\text{in}[/tex] and [tex]D_\text{out}[/tex] denote these two distances, and let [tex]F_\text{in}[/tex] and [tex]F_\text{out}[/tex] denote the input and the output forces. If the lever is indeed idea, then:
[tex]F_\text{in} \cdot D_\text{in} = F_\text{out} \cdot D_\text{out}[/tex].
Rearrange to obtain:
[tex]\displaystyle F_\text{in} = F_\text{out} \cdot \frac{D_\text{out}}{D_\text{in}}[/tex]
Class two levers are levers where the perpendicular distance between the fulcrum and the input is greater than that between the fulcrum and the output. For this ideal lever, that means [tex]D_\text{in} > D_\text{out}[/tex], such that [tex]F_\text{in} < F_\text{out}[/tex].
Despite [tex]F_\text{in} < F_\text{out}[/tex], the amount of work required will stay the same. Let [tex]s_\text{out}[/tex] denote the required linear displacement for the output force. At a distance of [tex]D_\text{out}[/tex] from the fulcrum, the angular displacement of the output force would be [tex]\displaystyle \frac{s_\text{out}}{D_\text{out}}[/tex]. Let [tex]s_\text{in}[/tex] denote the corresponding linear displacement required for the input force. Similarly, the angular displacement of the input force would be [tex]\displaystyle \frac{s_\text{in}}{D_\text{in}}[/tex]. Because both the input and the output are on the same lever, their angular displacement should be the same:
[tex]\displaystyle \frac{s_\text{in}}{D_\text{in}} =\frac{s_\text{out}}{D_\text{out}}[/tex].
Rearrange to obtain:
[tex]\displaystyle s_\text{in}=s_\text{out} \cdot \frac{D_\text{in}}{D_\text{out}}[/tex].
While increasing [tex]D_\text{in}[/tex] reduce the size of the input force [tex]F_\text{in}[/tex], doing so would also increase the linear distance of the input force [tex]s_\text{in}[/tex]. In other words, [tex]F_\text{in}[/tex] will have to move across a longer linear distance in order to move [tex]F_\text{out}[/tex] by the same [tex]s_\text{out}[/tex].
The amount of work required depends on both the size of the force and the distance traveled. Let [tex]W_\text{in}[/tex] and [tex]W_\text{out}[/tex] denote the input and output work. For this ideal lever:
[tex]\begin{aligned}W_\text{in} &= F_\text{in} \cdot s_\text{in} \\ &= \left(F_\text{out} \cdot \frac{D_\text{out}}{D_\text{in}}\right) \cdot \left(s_\text{out} \cdot \frac{D_\text{in}}{D_\text{out}}\right) \\ &= F_\text{out} \cdot s_\text{out} = W_\text{out}\end{aligned}[/tex].
In other words, the work input of the ideal lever is equal to the work output.
The efficiency of a machine can be measured as the percentage of work input that is converted to useful output. For this ideal lever, that ratio would be [tex]100\%[/tex]- not anything higher than that.
On the other hand, non-ideal levers take in more work than they give out. The reason is that because of resistance, [tex]F_\text{in}[/tex] would be larger than ideal:
[tex]\displaystyle F_\text{in} = F_\text{out} \cdot \frac{D_\text{out}}{D_\text{in}} + F(\text{resistance})[/tex].
As a result, in real (i.e., non-ideal) levers, the work input will exceed the useful work output. The efficiency will go below [tex]100\%[/tex],
The digigram shows a vertical number line.
What is the position of point X?
х
016
-12
12
16
0
Answer:
16
Explanation:
The position of X is 16 because they gap between -4 and 0 is 4.
2 decaliters + 800 deciliters = __________ liters?
Answer:
800 +2 is 802 is decilitre
o.802 is in l
Science occupations can have a significant impact on the economic success of a business.
True
False
Answer:
true
Explanation:
i just took the test
Answer:
TRUE!!!!!
Explanation:
TRUE!!!!!
TRU!!!!!!
TR!!!!!!
T!!!!!!
3) For the graph on the right, the graphical representation between speed and mass could best be described as: A. The speed of fall is directly proportional to the mass. B. The speed of the fall is proportional to the square root of the mass. C. The speed of fall is inversely proportional to the mass. D. The speed of the fall is proportional to the square of the mass. E. There is no relationship between the speed of fall and mass. speed of fall mass
Answer:
B
Explanation:
KE=0.5mv^2
The speed is inversely proportional to the square root of mass
A car is traveling South on I-85. It travels between two exits that are 5.40 km apart in 4.85 minutes. What is the average velocity of the car in m/s?
Answer: 18.56 m/sec
Explanation:
Average velocity =distance/time=5400/(4.85*60)=18.56 m/sec
Convert 8.1 kilograms to grams
Answer:
8100 g
Explanation:
8.1 kg × 1000
= 8100 g
Answer:
8,100 Grams
Explanation:
To change Kilograms to Grams, you multiply the mass value by 1000.
So, 8.1kg x 1000 = 8,100g.
Hope this helps!
sketch a velocity time graph for the motion of the body . from the graph explain each step, calculate the total distance covered by the body
Answer: please find the attached file for the solution.
Explanation:
In a velocity time graph for the motion of the body, the total distance covered by the body is area under the graph.
Please find the attached file for the solution.
Imagine you and a friend are trying to rearrange the furniture in your classroom. You push on a desk with a force of 150 N to the right. Your friend pushes on the same desk with a force of 50 N to the left. What is the net force on the desk
Answer:
100N
Step-by-step explanation:
If I push on a desk with a force of 150 N to the right and my friend pushes on the same desk with a force of 50 N to the left, this means that I pushed the desk in the positive x direction and the force I applied is F1 = +150N; my friend pushes the desk in the negative x direction and the applied force will be F2 = -50N.
The net force will the sum total of both forces acting on the desk.
Net force F = F1+F2
Given F1 = +150N and F2 = -50N
Net force F = +150N+(-50N)
Net force F = +150N-50N
Net force F = +100N
This answer is not mine so credits to abidemiokin
Which of the following is an example of a primary source?
A. Scientific journal
B. Dictionary
C. Encyclopedia
D. Newspaper
Answer:
scientific journal
in my guess
Answer:
scientific journalExplanation:
What energy is directly dependent upon velocity and mass?
A mechanical energy
O B. total energy
C. potential energy
O D. kinetic energy
Answer:
Kinetic energy
Explanation:
Define investigation to show its scientific meaning.
Answer:
the action of investigating something or someone; formal or systematic examination or research.
Explanation:
This definition is provided by Oxford Languages
50 POINTS
A graph of velocity versus time for an object shows a straight line with positive slope. What does that indicate about the acceleration of the object?
- the acceleration is changing
- the acceleration is zero
- the acceleration is constant and positive
Answer:
The acceleration is constant and positive
Explanation:
The straight line indicates that the acceleration is constant, while the positive slope indicates that the line is positive.
Answer:
^^^
Explanation:
An object falls freely from height H. if it takes one second to travel last half of total displacement find height H priop to the fall.
Answer:9.82 m
Explanation:
As we know from equation of motion
S=v*t +0.5 a t^2
Know s=H/2
a =9.82
t=1
V=0
Plugging the values
H*0.5=0+0.5*9.82*1^2
H=9.82 m
I'm taking physics and trying to figure out the 4 questions to this problem.
Answer:
Explanation:
At t = 1 velocity = 0
At t = 3 velocity = 3
slope of the line = 3-0 / 3-1 = 3/2
At t = 2
velocity = 3/2 x ( 2 - 1 )
= 1.5 m /s
velocity at t = 2 is 1.5 m /s
Position at t = 2 :
displacement at t = 2
area of graph upto t = 2
= 1 / 2 x 1 x 1.5 = .75
position at t = 2 :
= initial position + displacement
= 10 + .75 = 10.75 m
position at 6 s :
displacement at t = 6
area of curve upto t = 6
= 1 / 2 x 2 x 3 + 3 x 3 + 1/2 x 3 x ( 4.5 - 3 )
= 3 + 9 + 2.25
= 14.25 m
position at t = 6
= initial position + displacement
= 10 + 14.25 = 24.25 m
position at 9 s :
displacement at t = 9
area of curve upto t = 9
= 1 / 2 x 2 x 3 + 4 x 3 + 1/2 x 4 x ( 5 - 3 )- 1/2 x 2 x 1.5
= 3 + 12 + 4 - 1.5
= 17.5 m
position at t = 9
= initial position + displacement
= 10 + 17.5 = 27.5 m
.2, A car starting from rest has an acceleration of
0.5m/s2, what will be its final velocity after 5
seconds? What distance will be covered by
the car at the end of 5 seconds?
Answer: 2.5 m/s and 6.25 m
Explanation:
u = 0
a = 0.5 m/s²
t = 5 s
v = u + at
= 0 + 0.5 × 5
= 2.5 m/s
s = ut + 1/2 at²
= 1/2 × 2.5 × 5
= 6.25 m
somebody PLEASE help me on this DO NOT waste my answers PLEASE HELP ITS URGENT
This is integrated Physics and Chemistry
Answer:
#1: 8.92 x 10^6 = 8920000
#2: 3.05 x 10^-3 = 0.00305
Explanation:
You walk 20 feet. What is this distance in centimetres? 0.305 m 100 cm ----------- ----------- 1 ft 1 m
Answer:
609.6 cm is the answer
You are riding in a spaceship that has no windows, radios, or other means for you to observe or measure what is outside. You wish to determine if the ship is stopped or moving at constant velocity. What should you do
Answer: give up because nothing can be done.
Explanation:
You would have to give up because you have taken on an impossible task. And nothing can be done because there is no known means available to you to measure or observe what is happening outside the spaceship. And as a result this has made it an impossible task knowing the velocity of the ship or finding out.
Scientific models have two basic types. Please select the best answer from the choices provided T F
Answer:
Scientific models have two basic types. FALSE.
Hoped I helped
how will the pandemic change our life?
What is true of daylight hours at locations north and south of the equator? Days are longer than nights north of the equator. Nights are longer than days south of the equator. The length of days and nights change with the seasons.
Answer:
The length of days and nights change with the seasons.
Explanation:
Distance from the equator along with the tilt of Earth's rotational axis contributes to day and night period differences. Daylight hours or the period of sunlight exposure vary due to the inclined axis of the latitudes. In the northern hemisphere during summers, the tilt of the axis is towards the sun which brought more sunlight to the exposed region. And therefore the length of day hours is more than the southern hemisphere which at the same time will be tilted away from the sun.
Answer:
pablo
Explanation:
si pablo come tacos con barbacoa
6. I ran 12.2 km in 1.4 hours. Then I ran another 19.3 km uphill in 2.2 hours. What was my average speed?
Answer: 8.75 km/hr
Explanation:
Concept to know
Average speed: total distance/total time
-------------------------------------------------------
total distance/total time
=(12.2+19.3)/(1.4+2.2) ⇔ add the numbers of two time running together
=31.5/3.6 ⇔ simplify
=8.75 km/hr
Hope this helps!! :)
Please let me know if you have any question
Put a ball on the floor what forces are acting on it
Answer: Gravity
Explanation: Gravity is pulling down on the ball, making it stay on the floor
If three forces are equal and thier resultant force is zero, then measure of its internal angle is _____
Answer:
45 degrees
Explanation:
When 10 N force applied at 30 degrees to the end of a 20 cm handle of a wrench, it was just able to loosen the nut. What magnitude of the force would require to just loosen the nut, if the force apply perpendicularly at the end of the handle
Answer:
5NExplanation:
To get the magnitude of the force would require to just loosen the nut, if the force apply perpendicularly at the end of the handle, we will have to resolve the force perpendicular to the wrench. Torque is the turning effect of a body or force about a point. It is similar to moments.
Torque = Force * radius
Note that the force must be perpendicular to the wrench. On resolving the force perpendicularly to the wrench, we will have to resolve the force to the vertical.
Fy = Fsinθ
Fy = 10sin30°
Fy = 10 * 0.5
Fy = 5N
Torque = Fy * r
Given Fy = 5N and r = 20cm = 0.2m
Torque = 5 * 0.2
Torque = 1Nm
Hence the magnitude of the force would require to just loosen the nut, if the force apply perpendicularly at the end of the handle is 5N
this is a device used to change the flow of electricity through a circuit
Answer:
Transformers are devices used in electrical circuits to change the voltage of electricity flowing in the circuit. Transformers can be used either to increase the voltage or decrease the voltage.
Calculate the speed of an 90,000 kg airplane with a kinetic energy of one billion Joules.
Answer:
Kinetic energy=1/2 mv^2.
which is 1,000,000,000=1/2×90,000×v^2.
1000000000=45,000v^2.
v^2=222.22.
v=√222.22.
v=14.9~15m/s.
The speed of a 90,000 kg airplane with a kinetic energy of one billion Joules would be 149.07 m/s
What is mechanical energy?
Mechanical energy is the combination of all the energy in motion represented by total kinetic energy and the total potential energy stored energy in the system which is represented by total potential energy.
Total mechanical energy is s the sum of all the kinetic as well as potential energy stored in the system.
ME = KE + PE
As given in the problem we have to calculate the speed of an airplane with a mass of 90,000 kg and kinetic energy of one billion Joules.
m= 90000 kg
K.E = 1 billion Joules
= 1,000,000,000 Joules
The total kinetic energy
KE = 1/2mv²
By substituting the respective values in the formula of kinetic energy
1,000,000,000 J = 1/2×90000 ×v²
v² = 1,000,000,000 ×2/90000
v² = 22222.222
v =149.07 m/s
Thus, the speed of a 90,000 kg airplane with a kinetic energy of one billion Joules would be 149.07 m/s
Learn more about mechanical energy from here
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