please help ASAP.
these are examination questions ..
no nonsense answers .
i will mark as brainliest if you got it correct .​

We have that the time, to the nearest minute, when the water level is at 1.125 m for the second time after midnight is

[tex]t=10.0hours[/tex]

From the Question we are told that

Maximum height [tex]h_{max}=3m[/tex]

Minimum height  [tex]H_{min}=0.5m[/tex]

Time for  next high tide will occur[tex]T=12 hours =>720 min[/tex]

Generally Average Height

[tex]h_{avg}=\frac{3+0.5}{2}\\\\h_{avg}=1.75[/tex]

Therefore determine Amplitude to be

[tex]A=h_{max}=j_{avg}\\\\A=3-1.75\\\\A=1.25[/tex]

Generally, the equation for Time is mathematically given by

At t=0

[tex]h(x)=Acos(Bx)+h_{avg}[/tex]

Where

[tex]B=\frac{2\pi}{P}\\\\B=\frac{2\pi}{720}\\\\B=8.73*10^{-3}[/tex]

Therefore

[tex]h(t)=Acos8.73*10^{-3}(t)+h_{avg}[/tex]

Hence the Time at [tex]T=1.125[/tex] is

[tex]1.125(t)=1.25cos(8.73*10^{-3})(t)+1.75[/tex]

[tex]-0.1249t=1.75[/tex]

[tex]t=10.0hours[/tex]

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Answer:

There are many possible causes of magnetic defects in credit cards. But there are two direct causes: 1. Close to a strong magnet 2. Damage from scratches or wear Even if used properly it can cause magnetic defects. But if used incorrectly, it can cause an immediate relapse. If you have never used a credit card due to magnetic defects, check what will cause magnetic defects and for example credit cardMagnetic stripe cards, such as credit cards and cash cards, are more likely to cause magnetic field defects if brought near magnetically generating objects such as magnets. Although exposure to strong magnets does not necessarily lead to failure. However, it should be kept away from objects that may cause magnetic field defects.

Explanation:

Magnetic fields can erase or distort the data stored on these items. The correct option is A.

Magnetic media are used to store information in a magnetic format on audiotapes, credit cards, and videotapes. They may have their magnetic patterns and particle alignment disturbed if they are placed close to a powerful magnet.

The stored data may be lost or damaged as a result. For instance, credit cards' magnetic stripes may become illegible, audiotapes may lose their sound quality or possibly be completely erased, and videotapes may have distorted or scrambled imagery and audio.

To preserve the accuracy and utility of the data they contain, it is crucial to keep these things away from strong magnetic fields.

Thus, the correct option is A.

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Your question seems incomplete, the probable complete question is:

Why audiotape, credit cards and videotape not placed closed to a strong magnet

A. Magnetic fields can erase or distort the data stored on these items.

B. Magnetic fields can cause these items to become permanently demagnetized.

C. Magnetic fields can cause these items to generate excess heat and potentially catch fire.

D. Magnetic fields can cause these items to emit harmful radiation.

Answer:

The output force would decrease since exerted force is inversely proportional to contact area.

Explanation:

F ∝ [tex]\frac{1}{A}[/tex] , Where 'F' is the exerted force and 'A' is the contact area.

Answer:

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Explanation:

Answer:D.Keeping track of the exact amount of wind on each plant

Explanation:

Hi, there!!

Energy is defined as the capacity or ability to do work. It's SI unit is Joule.

here,

Joule = (kg×m×m)/(s×s)

= kg×m^2/s^2.

Therefore, the derived unit is kg.m^2 by s^2.

Hope it helps...

5 N

Archimedes' Principle

25 N

Answer:

Take up space

Explanation:

Actually we know this by the definition of matter which states that "matter is any substance that has mass and takes up space by having volume."

hope it helped you:)

Answer:

Explanation:

where W-weight, m-mass of the object and g-acceleration produced due to the earth's gravity. ... This happens because the normal reaction force exerted on the object in the lift is equal to zero, and normal force equals to mg, which in turn equals the weight of the object.

check the pictures(2 pictures)check the pictures(2 pictures)check the pictures(2 pictures)

The vector sum of the two forces is 20  and the magnitude of the resultant is 20 towards positive x-axis.

A vector is a quantity or phenomena with magnitude and direction that are independent of one another. The phrase also refers to a quantity's mathematical or geometrical representation.

If no vector can be written as a linear combination of the others, a set of vectors is said to be linearly independent.

The vector representation for the forces F and F are:

[tex]\rm \vec F_1 = 20 COS 60^0 \vec i + 20 SIN 60^0 \vec j\\\\ F_1 =20 \times \frac{1}{2} \vec i+20 \times \frac{\sqrt{3} }{2} \vec j \\\\ \vec F_1 = 10 \vec i+ 10 \sqrt{3} \vec J[/tex]

[tex]\rm F_2 = 20 cos 60^0 \vec i+20 sin(-60) \vec j \\\\ F_2 = 20 \times \frac{1}{2} \times \vec i+20 \times \frac{\sqrt{3} }{2} \vec j \\\\ \vec F_2 = 10 \vec I -10\sqrt{3} \vec J[/tex]

The vector sum of the two forces are;

[tex]\rm \vec R = \vec F_1+\vec F_2\\\\ \vec R = 10 \vec i+ 10 \sqrt{3} \vec J+10 \vec i-10\sqrt{3} \vec J\\\\ \vec R =20 i[/tex]

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Answer:

Choose B

Explanation:

Hope Can I help you

Answer:

First, as you may know, the light travels at a given velocity.

In vaccum, this velocity is c = 3x10^8 m/s.

And we know that:

distance = velocity*time

Now, if some object (like a star ) is really far away, the light that comes from that star may take years to reach the Earth.

This means that the images that the astronomers see today, actually happened years and years ago (So the night sky is like a picture of the "past" of the universe)

Also, for example, if an astronomer sees some particular thing, he can apply a model (a "simplification" of some phenomena that is used to simplify it an explain it) and with the model, the scientist can infer the information of the given thing some time before it was seen.

The astronomers could know what was happening inside galaxies way back then by the fact that;

they examine the spectra of galaxies (or the overall colors of galaxies) with the highest redshifts they can find

Astronomers Measure the wavelength of the light that is stretched, so the light is seen as 'shifted' towards the red part of the spectrum by using spectroscopy. This measure is also called redshift.

This invokes a ray of light through a triangular prism that splits the light into various components known as spectrum.

The way the astronomers could use this concept to know what was happening in the galaxies before is by examining the spectra of galaxies that have the highest redshifts.

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Answer:

The impulse exerted by one cart on the other has a magnitude of 4 N.s.

Explanation:

Given;

mass of the first cart, m₁ = 2 kg

initial speed of the first car, u₁ = 3 m/s

mass of the second cart, m₂ = 4 kg

initial speed of the second cart, u₂ = 0

Let the final speed of both carts = v, since they stick together after collision.

Apply the principle of conservation of momentum to determine v

m₁u₁ + m₂u₂ = v(m₁ + m₂)

2 x 3 + 0 = v(2 + 4)

6 = 6v

v = 1 m/s

Impulse is given by;

I = ft = mΔv = m(

The impulse exerted by the first cart on the second cart is given;

I = 2 (3 -1 )

I = 4 N.s

The impulse exerted by the second cart on the first cart is given;

I = 4(0-1)

I = - 4 N.s (equal in magnitude but opposite in direction to the impulse exerted by the first).

Therefore, the impulse exerted by one cart on the other has a magnitude of 4 N.s.

Answer:

(I). The Schwarzschild radius is [tex]2.94\times10^{8}\ km[/tex]

(II). The Schwarzschild radius is 17.7 km.

(III). The Schwarzschild radius is [tex]1.1\times10^{-7}\ km[/tex]

(IV). The Schwarzschild radius is [tex]7.4\times10^{-29}\ km[/tex]

Explanation:

Given that,

Mass of black hole [tex]m= 1\times10^{8} M_{sun}[/tex]

(I). We need to calculate the Schwarzschild radius

Using formula of radius

[tex]R_{g}=\dfrac{2MG}{c^2}[/tex]

Where, G = gravitational constant

M = mass

c = speed of light

Put the value into the formula

[tex]R_{g}=\dfrac{2\times6.67\times10^{-11}\times1\times10^{8}\times1.989\times10^{30}}{(3\times10^{8})^2}[/tex]

[tex]R_{g}=2.94\times10^{8}\ km[/tex]

(II). Mass of block hole [tex]m= 6 M_{sun}[/tex]

We need to calculate the Schwarzschild radius

Using formula of radius

[tex]R_{g}=\dfrac{2MG}{c^2}[/tex]

Put the value into the formula

[tex]R_{g}=\dfrac{2\times6.67\times10^{-11}\times6\times1.989\times10^{30}}{(3\times10^{8})^2}[/tex]

[tex]R_{g}=17.7\ km[/tex]

(III). Mass of block hole m= mass of moon

We need to calculate the Schwarzschild radius

Using formula of radius

[tex]R_{g}=\dfrac{2MG}{c^2}[/tex]

Put the value into the formula

[tex]R_{g}=\dfrac{2\times6.67\times10^{-11}\times7.35\times10^{22}}{(3\times10^{8})^2}[/tex]

[tex]R_{g}=1.1\times10^{-7}\ km[/tex]

(IV). Mass = 50 kg

We need to calculate the Schwarzschild radius

Using formula of radius

[tex]R_{g}=\dfrac{2MG}{c^2}[/tex]

Put the value into the formula

[tex]R_{g}=\dfrac{2\times6.67\times10^{-11}\times50}{(3\times10^{8})^2}[/tex]

[tex]R_{g}=7.4\times10^{-29}\ km[/tex]

Hence, (I). The Schwarzschild radius is [tex]2.94\times10^{8}\ km[/tex]

(II). The Schwarzschild radius is 17.7 km.

(III). The Schwarzschild radius is [tex]1.1\times10^{-7}\ km[/tex]

(IV). The Schwarzschild radius is [tex]7.4\times10^{-29}\ km[/tex]

The energy conservation allows to find the Schwarschild radius for several bodies of different masses are:

  1)  Black hole quasar is:  r = 2.9 10⁸ km

  2) Blsck hole supernove is:  r = 17.7 km

  3)  Mini black hole is:   r = 1.1 10⁻⁷ km

  4) Human body is:  r=  7 10⁻²⁹ km

The schwarschild radius is defined as the distance from a black hole center at radius  which the escape velocity is equal to the light speed, in some cases it is also called the event horizon.

Let's use Newton's second law where force is the universal law of attraction and acceleration is centripetal.

        F = ma

        F = [tex]G \frac{Mm}{r^2}[/tex]        

Where F is the force, M the mass of the black hole, m the handle of the body, r the radius and v the speed of the body.

The energy of the gravitational field is

        F = [tex]- \frac{dU}{dr }[/tex]  

         U = [tex]-G \frac{Mm}{r}[/tex]  

Let's use conservation of energy

        Em₀ = K + U = ½ m v² -  [tex]G \frac{Mm}{r}[/tex]  

In infinity the energy

        Em_f = 0

energy is conserved

       Em₀ = Em_f  

       ½ m v² - [tex]G \frac{Mm }{r}[/tex]  = 0

       r = [tex]\frac{2GM}{v^2}[/tex]

From the definition of the Schwarschild radius this speed is equal to the light speed

        v = c

        r = [tex]\frac{2GM}{c^2 }[/tex]  

They ask to calculate the radius for several cases of different mass, claculate the constant value

      V = [tex]\frac{2 \ 6.67 \ 10^{-11} }{(3 \ 10^8) ^2 }[/tex]  

      V =  1.482 10⁻²⁷

1) A black hole of mass M = 1 10⁸ [tex]M_{sum}[/tex]

The tabulated mass of the sun is [tex]M_{sum}[/tex] = 1.989 10³⁰ kg

Let's  substitute

        r =  1.482 10⁻²⁷   1 10⁸ 1.989 10³⁰

        r = 2.94 10⁸ km

With two significant figures

        r = 2.9 10⁸ km

2) A black hole of mass M = 6 [tex]M_{sum}[/tex]

        r =  1.482 10⁻²⁷ 6 1.989 10-30

        r = 17.7 km

3) a mini black hole with the mass of the moon

    Tabulated mass of the moon M = 7.35 10²² kg

       r =  1.482 10⁻²⁷  7.35 10²²    

       r = 1.1 10⁻⁷ km

4) A person of M = 50 kg

    r =  1.482 10⁻²⁷ 50

    r=  7 10-29 km

In conclusion using the conservation of energy we can find the Schwarschild radius for several bodies of different masses are:

  1)  Black hole quasar is:  r = 2.9 10⁸ km

  2) Blsck hole supernove is:  r = 17.7 km

  3)  Mini black hole is:   r = 1.1 10⁻⁷ km

  4) Human body is:  r=  7 10⁻²⁹ km

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Answer:

The answers to your questions are given below

Explanation:

A. Definition of momentum.

Momentum of an object can be defined as the product of the mass of the object and its velocity. Mathematically, it expreessed as:

Momentum = mass x Velocity

From the above equation, we can derive the SI unit of momentum as follow:

Mass is measured in Kilogram (Kg)

Velocity is measured in meter per second (ms¯¹).

Momentum = mass x Velocity

Momentum = Kg x ms¯¹

Momentum = Kg•ms¯¹

Therefore, the SI unit of momentum is Kg•ms¯¹.

Bi. Determination of the force of the body from O to A.

Mass (m) = 5 kg

Velocity (v) = 40 ms¯¹

Time (t) = 2 secs.

Force (F) =?

Next, we shall determine the acceleration of the body.

Acceleration (a) = Velocity (v) /Time (t)

a = v /t

Velocity (v) = 40 ms¯¹

Time (t) = 2 secs.

Acceleration (a) =.?

a = v/t

a = 40/2

a = 20 ms¯²

Now, we can obtain the force as follow:

Mass (m) = 5 kg

Acceleration (a) = 20 ms¯²

Force (F) =?

Force (F) = mass (m) x Acceleration (a)

F = ma

F = 5 x 20

F = 100 N

Therefore, the force of the body from O to A is 100 N.

Bii. Determination of the force of the body from B to C.

Mass (m) = 5 kg

Velocity (v) = 40 ms¯¹

Time (t) = 10 – 6 = 4 secs.

Force (F) =?

Next, we shall determine the acceleration of the body.

Acceleration (a) = Velocity (v) /Time (t)

a = v /t

Velocity (v) = 40 ms¯¹

Time (t) = 4 secs.

Acceleration (a) =.?

a = v/t

a = 40/4

a = 10 ms¯²

Now, we can obtain the force as follow:

Mass (m) = 5 kg

Acceleration (a) = 10 ms¯²

Force (F) =?

Force (F) = mass (m) x Acceleration (a)

F = ma

F = 5 x 10

F = 50 N

Therefore, the force of the body from B to C is 50 N.

Answer:

Fnet = F√2

Fnet = kq²/r² √2

Explanation:

A exerts a force F on B, and C exerts an equal force F on B perpendicular to that.  The net force can be found with Pythagorean theorem:

Fnet = √(F² + F²)

Fnet = F√2

The force between two charges particles is:

F = k q₁ q₂ / r²

where

k is Coulomb's constant, q₁ and q₂ are the charges, and r is the distance between the charges.

If we say the charge of each particle is q, then:

F = kq²/r²

Substituting:

Fnet = kq²/r² √2

Answer:

a) 0.73A

b) 0.23A

c) 2.76V

Explanation:

We need to first resolve the two resistors in series. The resistors in series are

12 Ω and 3 Ω  AND 6 Ω and 3 Ω

For  12 Ω and 3 Ω in series, total effective resistance =  12 Ω + 3 Ω = 15 Ω

For  6 Ω and 3 Ω in series, total effective resistance =  6 Ω + 3 Ω = 9 Ω

Since the equivalent series resistors i.e 15Ω ND 9Ω are connected in parallel, the total effective resistance Rt will be expressed as;

1/Rt = 1/15+1/9

1/Rt = (3+5)/45

1/Rt = 8/45

Rt = 45/8 Ω

a) If a potential difference of 4 V is applied across it, the total current I in the circuit can be derives using the ohms law.

According to the law E = IRt

Given E = 4V, Rt = 45/8

I = E/Rt

I = 4/(45/8)

I = 4 * 8/45

I = 32/45

I = 0.73A

Hence, the current drawn from the battery is 0.73A

b) Before we can calculate the current in the 12Ω resistor, we need to calculate the current in the equivalent resistance of 15Ω(sum of 12Ω and 3Ω)

Current in the 15Ω resistor = Voltage across the 15Ω resistor/Resistance

Current in the 15Ω resistor = 4/15

Current in the 15Ω resistor = 0.27A

Since the same current flows in a series connected resistors, hence the correct in the 12ohms resistor is also 0.27A.

c) Before we can calculate the pd across the 6ohms resistor, we need to know the voltage across the effective resistance of 9ohms(6ohms+3ohms). The pd across the 9ohm resistance will be the same as the source voltage i.e 4Volts.

We will need to share this 4volts between the 6ohms and the 3ohms using ohms law.

According to the law, V = IR

For the 6ohms resistor, voltage across it will be;

V = (0.73-0.27)×6

V= 0.46×6

V = 2.76Volts.

Hence the voltage across the 6ohms resistor is 2.76V.

Answer:

option b

Explanation:

the heavier one will have twice the kinetic energy of the lighter one

The heavier one will have twice the kinetic energy of the lighter one. Hence, option (B) is correct.

Given data:

The mass of object 1 is, m.

The mass of object 2 is, 2m.

Here, the concept of kinetic energy is used. The kinetic energy of an object is the energy possessed by the object by virtue of its motion. Motion means something related with the speed.

And the mathematical expression for the kinetic energy is given as,

[tex]KE =\dfrac{1}{2}mv^{2}[/tex]

Here,

m is the mass of body.

v is the speed of body.

Now considering the kinetic energy for the two given objects as,

[tex]KE=\dfrac{1}{2}mv^{2}\\\\KE'=\dfrac{1}{2}(2m)v^{2}[/tex]

Comparing both the values of kinetic energies, we find that,

KE' = 2KE

Thus, we can conclude that the heavier one will have twice the kinetic energy of the lighter one. Hence, option (B) is correct.

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Answer:

1,860

Explanation:

Explanation:

SI is the international system of units

It was developed to express magnitudes and quantities

Answer:

Matter can be identified through its properties. One clue to helps us identify matter is magnetism. Magnetism is the ability of a material to be attracted by a magnet. Only certain materials are attracted to magnets, like iron, nickel, and cobalt.

Explanation:

we can identify matter by:  physical properties  and

chemical properties

Answer:

The correct option is;

[tex]_{1}^{2}\textrm{He} + _{1}^{1}\textrm{H} \rightarrow _{3}^{2}\textrm{He} + energy[/tex]

Explanation:

The second step of the fusion process is the reaction (combination) where a Deuterium combines with a hydrogen to produce one helium 3, 3He, nucleus and a energy photon as follows;

[tex]_{1}^{2}\textrm{He} + _{1}^{1}\textrm{H} \rightarrow _{3}^{2}\textrm{He} +\gamma \ (energy)[/tex]

After which the produced Helium-3 combines to form the Helium nucleus an emit 2 protons

Steps 1 and 2 are take place two times (producing 26 MeV energy) before the step three (the combination of the formed helium-3) takes occurs.

Answer:

C on edge

Explanation:

Just did it and got it right :)

Answer:

fhaiisjrbekxkrkebxnsiiwj4bnds

Answer:

0.4113772 s

Explanation:

Given the following :

Mass of bullet (m1) = 8g = 0.008kg

Initial horizontal Velocity (u1) = 280m/s

Mass of block (m2) = 0.992kg

Maxumum distance (x) = 15cm = 0.15m

Recall;

Period (T) = 2π√(m/k)

According to the law of conservation of momentum : (inelastic Collison)

m1 * u1 = (m1 + m2) * v

Where v is the final Velocity of the colliding bodies

0.008 * 280 = (0.008 + 0.992) * v

2.24 = 1 * v

v = 2.24m/s

K. E = P. E

K. E = 0.5mv^2

P.E = 0.5kx^2

0.5(0.992 + 0.008)*2.24^2 = 0.5*k*(0.15)^2

0.5*1*5.0176 = 0.5*k*0.0225

2.5088 = 0.01125k

k = 2.5088 / 0.01125

k = 223.00444 N/m

Therefore,

Period (T) = 2π√(m/k)

T = 2π√(0.992+0.008) / 233.0444

T = 2π√0.0042910

T = 2π * 0.0655059

T = 0.4113772 s

The period of the simple harmonic motion (SHM) is 0.42 s.

The given parameters;

The final velocity of the system after the impact is calculated as follows;

[tex]m_1 u_1 + m_2u_2 = v(m_1 + m_2)\\\\0.008(280) \ + \ 0.992(0) = v(0.008 \ + \ 0.992)\\\\2.24 = v(1) \\\\v = 2.24 \ m/s[/tex]

The spring constant is calculated as follows;

[tex]\frac{1}{2} kx^2 = \frac{1}{2} mv^2\\\\k = \frac{mv^2}{x^2} \\\\k = \frac{(0.008 + 0.992))\times 2.24^2}{(0.15)^2} \\\\k = 223 \ N/m[/tex]

The angular speed of the simple harmonic motion (SHM) is calculated as follows;

[tex]\omega = \sqrt{\frac{k}{m} } \\\\\omega = \sqrt{\frac{223}{(0.008 + 0.992)} }\\\\\omega = 14.933 \ rad/s[/tex]

The period of the oscillation is calculated as follows;

[tex]T = \frac{2\pi }{\omega} \\\\T = \frac{2\pi }{14.933} \\\\T = 0.42 \ s[/tex]

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Answer:

40 cm

Explanation:

Magnification of a pinhole camera is given by;

M= height of image/ height of object

Since;

M= 0.25

Height of image = 6cm

Height of object = height of image / M

Height of object = 6/0.25 = 24 cm

Height of image/ height of object = distance of image from pinhole/ distance of object from pinhole

Since the distance of image from pinhole = 10cm

Let the distance of object from pinhole be x

6/24 = 10/x

6x = 240

x= 240/6

x = 40 cm

Answer:

585×10⁸ m

Explanation:

Distance = rate × time

d = (2.998×10⁸ m/s) (3.25 min) (60 s/min)

d = 585×10⁸ m

Answer:

is the last one, a magnetic wave and electrical current moving in opposite directions

Explanation:

opposite directions always attract in magnetic waves and fields

Answer:

The reading of the vernier calliper is 3.93 mm

Explanation:

The given instrument is a micrometer screw gauge that has a main scale reading and a vernier scale reading

The the question, we have;

The individual divisions of the main scale = 0.5 mm

The reading on the main scale = 3.5 mm

The reading on the vernier scale = 43

The accuracy of the vernier caliper = 0.01

Reading on the vernier scale multiplied by the accuracy of the vernier caliper = 43 × 0.01 = 0.43 mm

The reading of the micrometer screw gauge = The reading on the main scale + Reading on the vernier scale multiplied by the accuracy of the vernier caliper

Therefore, the reading of the micrometer screw gauge = 3.5 + 0.43= 3.93 mm

The reading of the vernier calliper = 3.93 mm.

Answer:

9 and 4

Explanation:

The relation is:

● r = s^2 / t^2

Triplind s means multiplying it by 3. Since it's an equation we should multiply both sides by the same number

Let k be the number we should multiply by r

●k* r = (3s)^2 / t^2

●k* r = 9s^2 /t^2

We have multiplied s^2 by 9 so we should do the same for r.

k = 9

■■■■■■■■■■■■■■■■■■■■■■■■■■

Doubling t means multiplying it by 2.

Let x be the number we shoukd multiply by r.

● x* r = s^2/(2t)^2

● x*r = s^2/ 4t^2

We have multiplied t^2 by 4 so we should do the same for r.

x= 4