Answer:
I think it could be C.
hope it helps!
3. A boat at sea is being moved by the ocean current at 5 metres/minute directly to the east. At the same time it is being moved directly to
the north at 3 metres/minute by a strong wind. Determine the magnitude and direction of the boat's overall velocity.
Explanation:
A boat at sea is being moved by the ocean current at 5 metres/minute directly to the east.
At the same time, it is being moved directly to the north at 3 metres/minute by a strong wind.
We need to find the magnitude and direction of the boat's overall velocity.
As both velocities are moving perpendicular to each other. The resultant velocity is given by :
[tex]v=\sqrt{5^2+3^2} \\\\=\sqrt{25}\\\\=5\ \text{metres/minute}[/tex]
For direction,
[tex]\tan\theta=\dfrac{v_y}{v_x}\\\\=\dfrac{3}5{}\\\\\theta=\tan^{-1}(\dfrac{3}5{})\\\\=30.96^{\circ}[/tex]
Hence, this is the required solutin.
i need help on this question.
Answer:
Answer: B. 49 N
Explanation:
Friction Force
When an object is at rest on a rough surface, it encounters a friction force that opposes motion.
The friction force when an object is moving on a horizontal surface is calculated by:
[tex]Fr=\mu_k N[/tex]
Where [tex]\mu_k[/tex] is the coefficient of static friction and N is the normal force.
If no forces other then the weight and the normal are acting upon the y-direction, then the weight and the normal are equal in magnitude:
N = W = m.g
Thus, the friction force is:
[tex]Fr=\mu_k W[/tex]
We are given the coefficient of static friction [tex]\mu_k=0.5[/tex] and the mass of the object m=10 Kg. The minimum force needed to make it start moving is the maximum friction force:
Fr=0.5*10*9.8
Fr = 49 N
Answer: B. 49 N
Free electromagnetic oscillations occur in an electrical circuit. Knowing the characteristic dimensions of the elements, L=20mH și C=0,005mF, determine: a)The period of free electromagnetic oscillations: b)Frequency of free electromagnetic oscillations: c)Electromagnetic energy in the circuit when the maximum value of the current intensity is equal to 100 mA.
Answer:
a. 0.199 ms b. 5.03 kHz c. 0.1 mJ
Explanation:
a. The period of oscillation of an L-C circuit is T = 2π√(LC) where L = inductance = 20 mH = 20 × 10⁻³ H and C = capacitance = 0.005 mF = 5 × 10⁻⁶ F.
So, T = 2π√(LC)
= 2π√(20 × 10⁻³ H × 5 × 10⁻⁶ F)
= 2π√(100 × 10⁻¹¹)
= 2π√(10 × 10⁻¹⁰)
= 2π(3.16 × 10⁻⁵)
= 19.87 × 10⁻⁵
= 1.987 × 10⁻⁴ s
= 1.99 × 10⁻⁴ s
= 0.199 × 10⁻³ s
= 0.199 ms
b. frequency , f = 1/T where T = period = 0.199 × 10⁻³ s.
So, f = 1/0.199 × 10⁻³ s
= 5.03 × 10³ Hz
= 5.03 kHz
c. The electromagnetic energy E = 1/2Li² where L = inductance = 20 × 10⁻³ H and i = current = 100 mA = 0.1 A
So, E = 1/2Li²
= 1/2 × 20 × 10⁻³ H × (0.1 A)²
= 0.1 × 10⁻³ J
= 0.1 mJ
Standing waves are created in the four strings shown in Figure 25. All strings have the same mass per unit length and are under the same tension The lengths of the strings are given. Rank the frequencies of the oscillations, from largest to smallest
Answer:
The rank of the frequencies from largest to smallest is
The largest frequency of oscillation is given by the string in option D
The second largest frequency of oscillation is given by the string in option B
The third largest frequency of oscillation is given by the string in option A
The smallest frequency of oscillation is given by the string in option C
Explanation:
The given parameters are;
The mass per unit length of all string, m/L = Constant
The tension of all the string, T = Constant
The frequency of oscillation, f, of a string is given as follows;
[tex]f = \dfrac{(n + 1) \times \sqrt{\dfrac{T}{m/L} } }{2 \cdot L}[/tex]
Where;
T = The tension in the string
m = The mass of the string
L = The length of the string
n = The number of overtones
[tex]Therefore, \ {\sqrt{\dfrac{T}{m/L} } } = Constant \ for \ all \ strings = K[/tex]
For the string in option A, the length, L = 27 cm, n = 3 we have;
[tex]f_A = \dfrac{(n + 1) \times \sqrt{\dfrac{T}{m/L} } }{2 \cdot L} = \dfrac{(3 + 1) \times K }{2 \times 27} = \dfrac{2 \times K}{27} \approx 0.07407 \cdot K[/tex]
For the string in option B, the length, L = 30 cm, n = 4 we have;
[tex]f_B = \dfrac{(n + 1) \times \sqrt{\dfrac{T}{m/L} } }{2 \cdot L} = \dfrac{(4 + 1) \times K }{2 \times 30} = \dfrac{ K}{12} \approx 0.08 \overline 3\cdot K[/tex]
For the string in option C, the length, L = 30 cm, n = 3 we have;
[tex]f_C = \dfrac{(n + 1) \times \sqrt{\dfrac{T}{m/L} } }{2 \cdot L} = \dfrac{(3 + 1) \times K }{2 \times 30} = \dfrac{K}{15} \approx 0.0 \overline 6 \cdot K[/tex]
For the string in option D, the length, L = 24 cm, n = 4 we have;
[tex]f_D = \dfrac{(n + 1) \times \sqrt{\dfrac{T}{m/L} } }{2 \cdot L} = \dfrac{(4 + 1) \times K }{2 \times 24} = \dfrac{5 \times K}{48} \approx 0.1041 \overline 6 \cdot K[/tex]
Therefore, we have the rank of the frequency of oscillations of th strings from largest to smallest given as follows;
1 ) [tex]f_D[/tex] 2) [tex]f_B[/tex] 3) [tex]f_A[/tex] 4) [tex]f_C[/tex]
The order of the frequencies is [tex]f_D>f_B>f_A>f_C[/tex]
Standing waves:The frequency of the standing wave in a string tied at both ends is given by:
[tex]f=\frac{nv}{2L}[/tex]
where n is the mode of frequency
v is the velocity of the wave
and L is the length of the string.
Now the velocity of a wave in a string tied at both ends is given by
[tex]v=\sqrt{\frac{T}{\mu}}[/tex]
where T is the tension and μ is the mass per unit length.
Since T and μ are the same for all the strings, velocity [tex]v[/tex] will be the same for all.
Now to find the mode of frequency we can calculate the number of nodes (including the nodes at the ends) in the given figure and subtract by 1. Nodes are the point where the amplitude of the wave is zero.
[tex]f_A=\frac{3v}{2\times27}=\frac{v}{18}\;s^{-1}\\\\f_B=\frac{4v}{2\times30}=\frac{v}{15}\;s^{-1}\\\\f_C=\frac{3v}{2\times30}=\frac{v}{20}\;s^{-1}\\\\f_D=\frac{4v}{2\times24}= \frac{v}{12}\;s^{-1}[/tex]
Hence, [tex]f_D>f_B>f_A>f_C[/tex]
Learn more about standing waves:
https://brainly.com/question/1698005?referrer=searchResults
pls I will give brainliest for correct answer
find the distance travelled im the first 8 hours
Answer
I think it is 112 havent done this in a while but im pretty sure thats it Good luck
Explanation:
If red and blue light rays fall with the same angle of incidence on the separating
surface between two different transparent media, then the ratio between the refraction
angle of the red light and the refraction angle of the blue light (.) is
a) greater than 1
b)equal to 1
c )indeterminable
d)less than 1
Answer:
I'm gonna say it's D
Explanation:
but when u do the experiment on in u head you'll actually find out that it is actually , indeterminable
marked as brainiest if correct
Answer:
I think the the answer is creating and layout and template style ( C )
Explanation:
I did it before and i was checking my notes and i wrote that down , Hope this Helps :)
Which of these materials is not magnetic?'
*
Cobalt
Iron
Copper
Stainless Steel
Answer:
stainless steel is the material which is non magnetic.
How is an emulsion different from other colloids?
The difference between colloid and emulsion is that a colloid can form when any state of matter (solid, liquid or gas) combine with a liquid whereas an emulsion has two liquid components which are immiscible with each other.
Answer:
wrthfnhdghkyulyf
Explanation:
zdfhdfhghdhddddddddddddddddddddd
Choose the element that has the larger atomic radius: francium or sodium.
Answer:
Francium.
I hope it will be useful.
Can you please help me with this physics question
Answer:
See the answers below
Explanation:
We can solve both problems using vector sum.
a)
Let's assume the forces that help the diver dive as positive downward, and the forces that oppose upward, as negative
[tex]F_{resultant}=100+30-85+900\\F_{resultant}=845[N][/tex]
The drag force is horizontal d this way in the horizontal direction we will only have the drag force that produces the water stream.
[tex]F_{drag}=50[N][/tex]
b)
Let's assume the forces that propel the rocket upwards as positive and forces like the weight of the rocket and other elements as negative forces.
[tex]F_{resultant}=960+7080-7700\\F_{resultant}=340 [kN][/tex]
An incidence that is caused by sleep and also occurs during sleep is known as a __________.
Answer:
parasomnia
Explanation:
Plzz Help easy quesion for 20 points Why does someone get burned if they touch an old filament bulb that has been on for a few hours? Plzz Help
Answer:
In reality, the filament gets so hot it in a real sense bubbles off molecules and electrons. Now and again this material gathers as a dull spot at the highest point of the bulb. Eventually, the filament falls apart, gets frail, and breaks, subsequently finishing the life of the light. Lights radiate light by siphoning an electric flow through a dainty tungsten fiber. The filament warms and emits light. Over the long haul, the filament oxidizes and turns out to be increasingly fragile, until it splits up and the bulb goes out. ... Tungsten picks up obstruction as it warms.
Hope this helped :)
The Fitness Log is:
A.
Fitness information presented in lesson format.
B.
A carefully considered essay response on a specified topic.
C.
A checklist of items to complete each section.
D.
A record of all the physical activity you complete in one week.
Answer:
D. A record of all the physical activity you complete in one week.
Explanation:
A "Fitness Log" allows you to keep track of your workout or exercise. Therefore, it is a record of the different workout you've managed to complete within a time frame. It gives you several information such as the type of workout you've completed, its duration and the time of the day it was performed. This makes a person motivated to exercise because he can see his progress. He may also include his mood before and after workout in order to become more mindful in exercising and many other things.
Answer:
the answer is D i just got the answer right
Explanation:
Which of the following is true about thoughts
Answer:
they can be unpredictable until you think it
Explanation:
Was the cannonball able to hit its target of 50 meters when the initial velocity was 20 m/s? Why?/Why Not?
(was not able to hit the target, but I don't know the reason)
Answer:
The cannon ball was not able to hit the target because the target is located at a height of 50 m whereas the cannon ball was only above to get to a height of 20 m.
Explanation:
From the question given above, the following data were obtained:
Height to which the target is located = 50 m
Initial velocity (u) = 20 m/s
To know whether or not the cannon ball is able to hit the target, we shall determine the maximum height to which the cannon ball attained. This can be obtained as follow:
Initial velocity (u) = 20 m/s
Final velocity (v) = 0 (at maximum height)
Acceleration due to gravity (g) = 10 m/s²
Maximum height (h) =?
v² = u² – 2gh (since the ball is going against gravity)
0² = 20² – (2 × 10 × h)
0 = 400 – 20h
Collect like terms
0 – 400 = – 20h
– 400 = – 20h
Divide both side by – 20
h = – 400 / – 20
h = 20 m
Thus, the the maximum height to which the cannon ball attained is 20 m.
From the calculations made above, we can conclude that the cannon ball was not able to hit the target because the target is located at a height of 50 m whereas the cannon ball was only above to get to a height of 20 m.
concave lens has negative focal length why
Se lanza un cuerpo verticalmente hacia arriba con una velocidad de 60m/s. Calcular a) Que altura se hallara el cuerpo al cabo de 2s, b)a qué altura máxima llega? C) cuánto tiempo se demora en llegar a la altura máxima y en qué tiempo regresa nuevamente al sitio donde fue lanzado.
Answer:
(a) 100.38 m
(b) 183.49 m
(c) 6.12 seconds and 12.24 seconds.
Explanation:
Given that a body is thrown vertically upwards with a velocity of 60 m/s.
Assuming that upward direction is positive
So, the initial velocity, u=60 m/s
As the acceleration due to gravity, g=9.81 m/s^2, acts in the downward direction, so
a=-9.81 m/s^2
(a) By using the equation of motion, the displacement of the body after time t=2 seconds, is
[tex]s=ut+\frac 1 2 at^2 \\\\ s=60\times 2 +\frac 1 2 (-9.81)2^2 \\\\[/tex]
s=100.38 m
Hence, the height of the body will be 100.38 m after 2 seconds.
(b) At the maximum height, the velocity of the object is zero, so
v=0.
The maximum height is the displacement of the body where it attains zero velocity.
Using the equation of the motion.
[tex]v^2=u^2+2as \\\\0= 60^2 +2(-9.81)s \\\\s=\frac {3600}{2\times 9.81} \\\\[/tex]
s=183.49 m
Hence, the maximum height of the body is 183.49 m.
(c) Time to reach the maximum height
v=u+at
0=60 +(-9.81)t
t=60/9.81
t=6.12 seconds.
The body will take 6.12 seconds to reach the maximum height.
As the time to reach the maximum height from the initial position is the same as the time to reach the initial position from the maximum height.
So, the total time to returns again to the place where it was launched
= 2 x 6.12 = 12.24 seconds.
If an elevator is moving at a speed of 5 m/s and the person in it is 82 kg what is the person’s kinetic energy?
Answer:
KE 1025J
[tex] \frac{1}{2} m {v}^{2} \\ [/tex]
Explanation:
[tex] \frac{1}{2} \times 82 \times {5}^{2} [/tex]
1025J
A 0N
B 6N
C 10 N
D 12 N
Answer:
The net force acting on the object is 0 N
Explanation:
Newton's Second Law of Forces
The net force acting on a body is proportional to the mass of the object and its acceleration.
The net force can be calculated as the sum of all the force vectors in each rectangular coordinate separately.
The image shows a free body diagram where four forces are acting: two in the vertical direction and two in the horizontal direction.
Note the forces in the vertical direction have the same magnitude and opposite directions, thus the net force is zero in that direction.
Since we are given the acceleration a =0, the net force is also 0, thus the horizontal forces should be in equilibrium.
The applied force of Fapp=10 N is compensated by the friction force whose value is, necessarily Fr=10 N in the opposite direction.
The net force acting on the object is 0 N
When the mallet hits the ball with an action force, the ball exerts a reaction 1 force on the mallet as explained by: 1) Newton's first law 2) Newton's second law 3) Newton's third law 4) all three of Newton's laws
Answer:
It's Newton's third law. For every known reaction, there is a equal and opposite reaction.
Explanation:
The mallet which hits the ball with an action force, the ball exerts a reaction force on the mallet as explained by the Newton's third law. Thus, the correct option is 3.
What is the Newton's third law?Newton's third law states that for every action (force) in nature there is an equal and opposite force or reaction. An example of third law of motion is that the mallet hits the ball with an action force, then the ball exerts a reaction.
If an object A exerts a force on the object B, then object B must also exert a force of equal magnitude and in the opposite direction back on object A. The law represents a certain symmetry in the nature that the forces always occur in pairs, and one body cannot exert a force on another without experiencing any kind of force itself.
Therefore, the correct option is 3.
Learn more about Newton's third law here:
https://brainly.com/question/29768600
#SPJ2
Longitudinal seismic waves are known as
a primary waves.
b. secondary waves.
surface waves.
d. transverse waves.
Please select the best answer from the choices provided
О А
ОВ
ОС
D
Answer:
A. primary waves
Explanation:
A ball is thrown directly upward with an initial speed of 72 m/s. How much time passes before the ball reaches the highest point it will ever reach
Answer:
7.35 seconds
Explanation:
The computation of the time passed prior to the ball reached to the highest point is as follows;
As we know that the acceleration because of gravity on earth is 9.8 m/s
As the ball is thrown directly in an upward direction with a speed of 72 m/s
So, the time passed prior to the ball reached to the highest point is
= 72 ÷ 9.8
= 7.35 seconds
Hence, the above represents the answer
What is horizontal motion
Horizontal motion is defined as a projectile motion in a horizontal plane depending upon the force acting on it. For a short distance, the vertical and horizontal components of a projectile are perpendicular and independent of each other.
Answer:
A projectile moves along its path with a constant horizontal velocity
calculate the resistance of a wire 150cm long and diameter 2.0mm constructed from an alloy of resistivity 44*10-⁸Ωm
Answer:
R = 0.21 Ω
Explanation:
the formula:
R = r x l/A
R = (44 x 10-⁸ Ωm) x 1.5 / (π x (1 x 10-³ m)²)
R = 6.6 x 10-⁷ / 3.14 x 10-⁶
R = 0.21 Ω
12. A rolling ball has 18 J of kinetic energy and is rolling 3.0 m/s. Find its mass.
Answer:
4g
I hope it will be useful.
Explanation:
KE = (1/2)*m*v^2
PLEASE PLEASE HELP ASAP
A cyclist speeds up from 3 m/s to 7 m/s in 8 seconds.
What is its change in velocity?
What's its acceleration?
Answer:
Change in velocity = 4 m/s and acceleration = 0.5 m/s²
Explanation:
Given that,
Initial velocity, u = 3 m/s
Final velocity, v = 7 m/s
Time, t = 8 seconds
(a) The change in velocity of a cyclist.
[tex]\Delta v=v-u\\\\=7\ m/s-3\ m/s\\\\=4\ m/s[/tex]
(b) Acceleration,
[tex]a=\dfrac{\Delta v}{t}\\\\a=\dfrac{4\ m/s}{8\ s}\\\\a=0.5\ m/s^2[/tex]
So, the change in velocity is 4 m/s and acceleration is 0.5 m/s².
If six moles of hydrogen chloride (HCl) react with plenty of aluminum, how many moles of aluminum chloride (AlCl3) will the reaction produce?
2Al + 6HCl → 2AlCl3 + 3H2
Answer:
Two moles of aluminum chloride [tex](AlCl_3)[/tex] are produced when six miles of hydrogen Chloride [tex](HCl)[/tex] react with plenty of aluminum
Explanation:
6 Moles of [tex]HCl[/tex] will only react with 2 moles of [tex]Al[/tex] irrespective of the number of moles of each compound present. The reaction wiil take place in this ratio only. The products produced will be 2 moles of [tex]AlCl_3[/tex] and 3 moles of [tex]H_2[/tex] this ratio will also be constant.
So, six moles of hydrogen chloride [tex](HCl)[/tex] will react with plenty of aluminum to produce many 2 moles of aluminum chloride [tex](AlCl_3)[/tex].
Sometimes you can see a faint reflection in the surface of a shiny plate or cup.Why ?
Answer:
The degree of reflection whether faint or bright you see on the surface of an object is an indication that light particles had hit the surface. Since light is a wave and as part of its characteristics can get reflected. However, the amount of light reflected by a surface is dependent on the smoothness of the surface which can be shiny or dull, it can also be dependent on the nature of the surface which can be glass, water, and so on. So, from the question, you can see a faint reflection on the surface of a shiny plate or cup because of the smoothness of the surface which reflects the lights that hit it from a particular direction at the same angle.
What are immiscible liquids?
Immiscible liquids are those which won't mix to give a single phase. Oil and water are examples of immiscible liquids - one floats on top of the other. It explains the background to steam distillation and looks at a simple way of carrying this out.