determine the design angle ϕ ( 0 ° ≤ ϕ ≤ 90 ° ) ϕ(0°≤ϕ≤90°) between members ab and ac so that the 400-lb horizontal force has a component of 600 lb which acts up to the right, in the direction from b toward a. also calculate the magnitude of the force component along ac. take

(a) Its instantaneous velocity at t = 10.0s is 0.4m/s.

(b) Its instantaneous velocity at t = 30.0s is 0.5 m/s.

(c) Its average velocity between t = 0 and t=5.0s is 0.6 m/s.

(d) Its average velocity between t = 25.0s and t=30.0s is 1.4 m/s.

(e) Its average velocity between t=40.0s and t=50.0s is -1 m/s.

Instantaneous velocity is defined as the velocity of an object under motion at a specific point of time.

at time, t = 10 seconds, x = 4 m

v = 4 m / 10 s = 0.4 m/s

at time, t = 30 seconds, x = 15 m

v = 15 m / 30 s = 0.5 m/s

v(avg) = Δx / Δt

v(avg) = (3 - 0)/(5 - 0) = 0.6 m/s

v(avg) = Δx / Δt

v(avg) = (15 - 8)/(30 - 25) = 1.4 m/s

v(avg) = Δx / Δt

v(avg) = (10 - 20)/(50 - 40) = -1 m/s

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In a two-d coordinate system, every vector can be broken down and considered as the x-component and y-component.

A vector quantity has two characteristics, a magnitude and a direction. And these two characteristics are accompanied by two components.

If the vector is V, then these components can be represented as vx and vy.

These vx and vy are the parts of the vector that are generated along the axes of the coordinate plane.

Any vector with a two-dimensional direction can be conceived of as having two distinct parts. A single vector's component specifies how that vector acts in a certain direction.

If the magnitude of the vector is given as a and the direction is given as [tex]\theta[/tex] of a two-dimensional vector, then the components of the vector can be found out using the following formulas:

vx=vcosθ for the x component

and

vy=vsinθ for the y component

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The capacitance of the capacitor varies with time. i'm doubtful if this RC circuit should be called a linear circuit.

According to the definition, a linear circuit obeys principle of superposition . The RC circuit with variable capacitor still obeys principle of superposition at any instant of time.

On the opposite hand, traditional analysis techniques for linear circuits might not be applicable for the analysis of this RC circuit.

A device or system is said to be time-invariant if and only if shifting in time its zero-state response by some constant always results in only shifting in time its zero-state response by that same constant, valid for all time, all possible inputs, and every one possible time shifts.

If the capacitance varies only with time, then that's a linear time-variant capacitor. If the resistance is constant or may be a function of time only, then that's a linear time-invariant or linear time-variant resistor respectively. therefore the RC network is linear time-variant. (It is time-variant due to the capacitor, whether the resistor is time-invariant or time-variant.)

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The magnitudes of the electric field at the following distance 0cm,10cm,40cm,72cm are 0,5.2 x 105 N/C,2.1 x 106 N/C and 6.42 x 105 N/C.

An electric field is a physical field that surrounds a charged particle and exerts a force on all other charged particles in the field to attract or repel each other. Electric fields are generated by electric charges and time-varying currents. Both electric and magnetic fields are manifestations of the electromagnetic field, one of nature's four fundamental interactions (also called forces). Electric fields are important in many areas of physics and are used in electrical engineering. For example, in atomic physics and chemistry, the electric field is the gravitational force that holds atomic nuclei and electrons together. It is also the force responsible for the chemical bonds between atoms that form molecules.

R = 40 cm = 0.4 m ; q = 31.9 \muC = 32 x 10-6 C ;

We need to find the expression for E field for given geometry.

from Gauss law,

(r). dA = Qin/ e0

E(r) \oint dA = Qin/ e0

E(r) . 4 pi r2 = Qin/ e0

E(r) = Qin/4 pi[tex]r^{2}[/tex]

For, Qin = Q (4 pi r3 / 4 pi R3) = Q (r/R)3 putting this in above equation

E(r) = Q r3/4 pir2

R3 = E(r) = Q r /4 piR3

E(r) =  Q r /4 pi R3 (1)

For, Qin = Q

E(r) = Q/4 pi r2   (2)

(a) Since r = 0 is r < R

Using 1

E(r) = E(0) = 0

(b) r = 0.1 m

Again using 1

E(r) = Q r /4 piR3

E(0.1) = 9 x 109 x  37 x 10-6 x 0.1 / (0.4)3 = 5.2 x 105 N/C

Hence, E(0.1) = 5.2 x 105 N/C

(c) r = 0.4 m

We will use (2) here

E(r) = Q/4 pi r2  

E(0.4) = 9 x 109 x  37 x 10-6 / (0.4)2 = 2.1 x 106 N/C

Hence, E(0.4) = 2.1 x 106 N/C

d)r =0.72 m

We will use (2) here

E(r) = Q/4 pi r2

E(0.72) = 9 x 109 x  37 x 10-6 / (0.72)2 = 6.42 x 105 N/C

Hence, E(0.4) = 6.42 x 105 N/C

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Answer:

a = (v2 - v1) / t

If the velocity is changing but not the magnitude of speed then

the change in velocity is directed perpendicular to the current velocity of the object

(An example is an object undergoing uniform circular motion where the speed of the object around the circle is constant but the change in velocity is always directed toward the center of rotation)

The amount of heat this resistor gives in 24 hours and heat fiux q is mathematically given as

Qd=4340.589 W/m^2

Q_t amp;=Q*time

amp;=1.2 *J*(24*3600)

Q_damp=03680J

Q_damp;=103.680

[tex]A_s &=\frac{\pi}{4} d^2 \times 2+\pi d L \\\\A &=\frac{\pi}{4} \times 0.4^2 \times 2+\pi \times 0.4 \times 2[/tex]

A amp;=2.764601 cm^2

[tex]\\\q &=\frac{1.2 \times 104^{+}}{2.764601}=4340.589(\mathrm{~W} / \mathrm{m})[/tex]

qamp;=4340.589mm^2

In conclusion,

Qd=103.680Jq

Qd=4340.589 W/m^2

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The pressure is 22.59 x 10⁵ Pa.

We need to know about pressure to solve this problem. Pressure is unit that describe how much force applied on a surface area. It can be determined as

P = F / A

where P is pressure, F is force and A is area.

From the question above, we know that

d = 0.39 cm = 0.0039 m

F = 27 N

Calculate the surface area of the nail

A = π . r²

A = π . (1/2 . d)²

A = π . (1/2 . 0.0039)²

A = 1.195 x 10¯⁵ m²

Determine the pressure

P = F / A

P = 27 / (1.195 x 10¯⁵ )

P = 22.59 x 10⁵ Pa

Hence, the pressure is 22.59 x 10⁵ Pa.

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The current motion of HNLC on Oahu compare to the direction of the pacific plate motion relative to the hawaiian hot spot over the past 42 million years is North direction.

Because of plate tectonics now the islands are moving more north compared to before.

The theory of plate tectonics is the modern update to continental drift(opens in new tab), an idea first proposed by scientist Alfred Wegener in 1912 which stated that Earth’s continents had "drifted" across the planet over time. Wegener didn't have an explanation for how continents could move around the planet, but researchers do now: Plate tectonics.

Plate tectonics is the theory that Earth's outer shell is divided into large slabs of solid rock, called “plates,” that glide over Earth's mantle, the rocky inner layer above Earth’s core. Earth’s solid outer layer, which includes the crust and the uppermost mantle, is called the lithosphere.

It is 100 km (60 miles) thick, according to the Encyclopedia Britannica(opens in new tab). Below the lithosphere is the asthenosphere a viscous layer kept malleable by heat deep within the Earth(opens in new tab). It lubricates the undersides of Earth's tectonic plates, allowing the lithosphere to move around.

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The magnitudes of these two vectors could be the same which could be 100 for each.

A vector quantity has both magnitude and direction. Some of the examples of vectors quantities are;

Given that two vectors of fixed magnitude, but variable direction, are added. the result has a minimum magnitude of 0 and a maximum magnitude of 200.

When the two vectors are parallel and move opposite direction to each other, the resultant will be zero. That is,

Resultant vector = 100 - 100 = 0

But when the two vectors are parallel and move in the same direction to each other, the resultant will be 200. That is,

Resultant vector = 100 + 100 = 200

Therefore, the magnitudes of these two vectors could be the same which could be 100 for each.

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Answer:

Help with what??

Explanation:

Explanation:

there is no question to answer..

The sound intensity [tex]I_1[/tex] a distance [tex]d_1[/tex] = 15.0 m from a chain saw is 0.280 [tex]W/m^2[/tex]The sound intensity [tex]I_2[/tex] a distance [tex]d_2[/tex] = 32.0 m from the chain saw will be [tex]0.0615W/m^2[/tex].

How to find the sound intensity at the given distance?

To find the sound intensity, following formula is used:

[tex]\frac{I_1}{I_2} =\frac{d_2^2}{d_1^2}[/tex]

We will substitute the numerical values, we get:

[tex]\frac{0.280}{I_2} =\frac{32^2}{15^2} \\I_2=\frac{15^2\times0.280}{32^2} =0.0615W/m^2[/tex]

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Answer:

The sum of the currents entering a junction equals the sum of the currents leaving a junction because no charge is lost.

Explanation:

The law of conservation of charge as proposed by Kirchoff ensures that the sum of currents entering and leaving a circuit are the same. Kirchoff's law asserts that the total current entering a circuit's junction is precisely equal to the total current exiting the same junction for a parallel line. Because no charge is lost, the currents have nowhere else to go. This implies that the algebraic total of ALL currents entering and exiting a junction must equal zero. Kirchoff’s first law is alternatively referred to as the law of conservation of charge.

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The nail head has a zero.39 cm diameter. You strike it with a hammer that has 27 N of force. at the nail head, there might be a stress head of 31100716.5 Pa.

Pressure P = Force(F) / Area(A)

On nail head = P = [tex]\frac{F}{\pi r^{2}}[/tex]

[tex]= \frac{f}{\pi (\frac{d}{2} )^{2} }[/tex]

[tex]= \frac{4F}{\pi d^{2} }[/tex]

[tex]P = \frac{25*4}{3.14*0.0032^{2} }[/tex]

= 3110071.65 Pa

Pressure at the end of the nail P = [tex]\frac{F}{A}[/tex]

[tex]P = \frac{25*4}{3.14*0.00032^{2} }[/tex]

P = 31100716.5 Pa

pressure is the ratio of the force applied perpendicularly to an object's surface to its location. Its abbreviation is "p" or "P."

A fluid column whose weight is similar to the fluid's strain is represented with the aid of the strain head.

The elevation head represents the gravitational capacity energy resulting from elevation, even as the pressure head reflects the energy because of pore fluid stress

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The rating of the branch-circuit protective device is affected when the conductors used are of a larger size than called for by the code of up the amps and up the AWG.

Branch circuit protection devices are also known as UL 489 circuit breakers.

These devices are tasked to provide protection to all sorts of circuit wiring by keeping in control the amps and AWG.

In addition to this, they also help prevent fire and electric shocks and are also suitable for electrical isolation.

During the maintenance period, they limit the flow of current and also serve as means to cut off the electricity supply.

If large-sized conductors are used then the performance of the branch-circuit protective device may get affected.

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The height of the cliff from the rock is thrown with an initial velocity of 8.2 m/s is 56.14 m

The formula for the downward vertical launch and the procedure we will use is:

y = V₀*t + (gt²) /2

Where:

Information about the problem:

With the information gave, we can calculate the height from the rock is thrown, using the formula of downward vertical launch:

y = V₀*t + (gt²) /2

y = (8.2 m/s * 2.65 s) + [9.8 m/s² *  (2.65 s)²] /2

y = (21.73 m) + [9.8 m/s² * 7.0225 s²] /2

y = (21.73 m) + 68.821 m /2

y = 21.73 m + 34.41 m

y = 56.14 m

In physics vertical launch is the motion described by an object that has been launched vertically in which the acceleration is the earth's gravitational force.

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The series combination will give you the resistance of 200ohm when two 100ohm resistances are connected.

Resistance is a device used to restrict the flow of the current. By using ohm's law the resistance is the ratio of the potential difference applied across the circuit and the current flowing through the circuit.

Given that you quickly need a 133-ω resistance value but only have a collection of 100-ω resistors.

For this case use the series combination of the resistances in which the resistances are connected in series by doing so the effect of resistance is increased.

R = R1 + R2

If you have two 100 ohm resistances connect them in the series.

R = R1 + R2

R = 100 + 100

R =200 ohm

Therefore, the series combination will give you a resistance of 200ohm when two 100ohm resistances are connected.

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A beaker (glass jar) contains 1 kg of water; when converted to a volume measurement it is the same as: 1,000 ml 1,000 l 1,000 cm 3

Volume of water in ml  = 1000 ml

Volume of water in cm³ =  100cm³

Given that

To find

So, According the question

We have

For convert it in volume, we can follow some simple steps

So, we know

            [tex]= \frac{1}{1000}[/tex]

       volume of water in m³  v = 0.001 m³

   3. Now volume of water in ml = 0.001 × 10⁶ = 1000 ml

   4 . Now volume of water in cm³ = 0.001 × 10⁵ = 100cm³

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The correct option is option (D) Was an excellent north pole star in 3,000 BC.

Thuban (/jubaen/), also known as Alpha Draconis or Draconis, is a binary star system. It is a faint star in the Northern Hemisphere’s night sky, but because it served as the north pole star from the fourth to the second millennium BC, it is noteworthy historically. Thuban is the only member of Johann Bayer’s secondary magnitude class in the constellation Draco, despite the fact that at its current apparent magnitude of 3.65, it is 3.7 times fainter than Gamma Draconis (formerly called Eltanin), the brightest star in the constellation, which Bayer placed in his tertiae magnitude class despite its current apparent magnitude of 2.24.Thuban’s positioning regard to the Big Dipper (also known as the Plough) asterism of Ursa Major makes it very simple to see in the night sky under ideal viewing conditions. The two inner stars, Phecda and Megrez, point to Thuban, which is located only 15 degrees of arc from Megrez.Thuban is not bright enough to be seen in locations with significant light pollution.  

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Tech B is correct as any coil of wire in an electrical system can produce hundreds of volts when it is de-energized, because of reverse voltage spike.

When there is no load attached and no current flowing, a voltage source (batteries, power supplies, etc.) is said to have an open circuit. It will always be greater than any voltage in a "closed circuit." The output voltage decreases as soon as you start drawing current from the source because of a voltage drop across that resistance.

Back EMF is the term for the reverse voltage spike that results from the coil's magnetic field collapsing when the armature moves away from coil after it has been de-energized (Electromotive Force).

Therefore, Tech B is correct as any coil of wire in an electrical system can produce hundreds of volts when it is de-energized, because of reverse voltage spike.

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Answer:

The capacitance of the capacitor with two plates of area 377 cm2377 cm2 each separated by a distance 11.5 cm.11.5 cm in microfarads is 2.90 * 10-16 µF

Explanation:

Capacitance is proportional to the physical size of the plates as indicated by the plate area, A, and inversely proportional to the distance between the plates. The plate separation is denoted as d. Capacitance is also related to the dielectric constant. Farads are used to express it.

Using the formula: C=εoA/d

Where C is capacitance

A is Area

d is distance

εo is the permittivity of free space

εo = 8.854 * 10-12 F/m

A= 377 cm2 =3.77m

d = 11.5 cm2= 0.115m

C= 8.854 * 10-12*3.77m2 /0.115 m2

C=290.26*10-12 F

C= 2.90 * 10-16 µF

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If the motion (or polarity of the magnet) is reversed, the direction of deflection in a galvanometer is also reversed.

An electromechanical device used to measure electric current is a galvanometer. Early galvanometers were not calibrated, but later models, known as ammeters, were, and could measure current flow more precisely.

If the motion (or polarity of the magnet) is reversed, the direction of deflection in a galvanometer is also reversed. This suggests that an emf is produced anytime the magnetic flux connected to a coil changes.

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The overall efficiency (in %) of the plant is 30% if the steam power plant with a power output of 150 MW consumes coal at a rate of 60 tons/h.

Efficiency is the capacity to achieve something or get the desired outcome without wasting resources, time, money, energy, or effort.

It is given that:

A steam power plant with a power output of 150 MW consumes coal at a rate of 60 tonnes per hour.

As we know,

Thermal efficiency Te = (W/Q)x100

m(coal) = 60 tons/h = 50/3 kg/s

The heating value of the coal is 30,000 kj/k = 30 MJ/kg

Q = (50/3)30

Q = 500 MW

Te = (150/500)100

Te = 30%

Thus, the overall efficiency (in %) of the plant is 30% if the steam power plant with a power output of 150 MW consumes coal at a rate of 60 tons/h.

The question is incomplete.

The complete question is:

A steam power plant with a power output of 150 MW consumes coal at a rate of 60 tonnes per hour. If the heating value of coal is 30,000 KJ/kg, determine the overall efficiency (in %) of the plant.

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Answer:

The acceleration of the ball (excluding air resistance) is

9.80 m/s^2 in the downward direction.

That's all that can be inferred from the problem as it is stated.

The x ray photons have 885234000 J of energy, and the g-ray photons have an energy of 5.57 x 10^12 J in a total of 1 mol of each of these.

The distance calculated over which a periodic wave's shape repeats itself is known as the wavelength in physics. This wavelength can be described as the space between waves' crests, particularly between electromagnetic or sound wave points.

The distance that any kind of a wave travels between its crests or troughs, it is known as its wavelength (which may be an electromagnetic wave, a sound wave, or any other wave).

Here we have to use the formula

E= hc/λ

To calculate energy of x-ray photons, we have

a) E = [6.626 x 10^(-34) x 3 x 10^8] / 0.135 x 10^(-9)

⇒ E= 1.47 x 10^(-15) J per photon

Using Avogadro's number, the energy calculated per mole can be calculated as

E= 1 mol x 6.022 x 10^23 x 1.47 x 10^-15

E= 885234000 J

Then for the energy of g-ray photons, can be calculated as

b) E = [6.626 x 10^(-34) x 3 x 10^8] / 2.15 x 10^(-14)

E= 9.25 x 10^-12 J per photon

Then using Avogadro's number, we have

E = 1 mol x 6.022 x 10^23 x 9.25 x 10^-12

E = 5.57 x 10^12 J

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The 'advanced' material that changes shape with an applied voltage is: a. piezoelectric

A piezoelectric material has the ability to transform electrical energy into mechanical energy and mechanical energy into electrical energy and  due to this can change its shape in response to applied voltage.

The piezoelectric materials are natural or synthetic crystals that do not have a defined center of symmetry. Some piezoelectric materials are found naturally as some crystals, ceramics, DNA, enamel and others.

These materials are classified into two groups:

Voltage is the quantity that expresses the amount of electricity that exists in an electrical circuit.

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At the instant a current of 0.20 a is flowing through a coil of wire, the energy stored in its magnetic field is 6.0 x 10-3 j. The self inductance of the coil will be 0.30 H.

What is self inductance?

An example of electromagnetic induction is the property of self-inductance. The definition of self inductance is something like induction of a voltage in a wire that carries current when the current in the wire is changing. In the instance of self-inductance, the circuit itself induces a voltage through the magnetic field produced by a changing current. The voltage is thus self-induced.

Given,

Current (I) = 0.20 A

Energy (U)= 6.0 x 10⁻³

By the equation,

U = 1/2 (LI²)

L = 2U/I²

Putting the values given in the above equation,

L = 2(6.0 x 10⁻³) / (0.20)²

L = 0.30

Hence, the self inductance in the coil is 0.30 H.

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The mass of silver chloride  be produced from 1.39 ll of a 0.209 mm solution of silver nitrate is 28.3g.

With the chemical formula AgCl, silver chloride is a substance. The poor solubility of this white crystalline solid in water is widely recognised. Silver chloride undergoes a conversion to silver upon lighting or heating, which is shown by the coloring of certain samples changing from grey to black or purple.

used to create alloys, polish mirrors, and electroplate metals. used as a countermeasure that, when combined with the toxin, produces a safe chemical product. utilised in pharmaceuticals, and photographic films employ silver salts.

[tex]2{\rm{AgN}}{{\rm{O}}_3}\left( {aq} \right) + {\rm{CaC}}{{\rm{l}}_2}\left( {aq} \right)\longrightarrow{{}}2{\rm{AgCl}}\left( s \right) + {\rm{Ca}}{\left( {{\rm{N}}{{\rm{O}}_3}} \right)_2}\left( {aq} \right)[/tex]

[tex]\begin{array}{l}\\{\rm{Molarity}} = \frac{{{\rm{Moles}}}}{{{\rm{Volume}}}}\\\\0.209{\rm{ M}} = \frac{{{\rm{Moles}}}}{{1.39{\rm{ L}}}}\\\\{\rm{Moles}} = \left( {0.209{\rm{ mol/L}}} \right)\left( {1.39{\rm{ L}}} \right)\\\\{\rm{ = 0}}{\rm{.198 mol}}\\\end{array}\\[/tex]

[tex]\frac{{\left( {0.198{\rm{ mol AgN}}{{\rm{O}}_3}} \right)\left( {2{\rm{ mol AgCl}}} \right)}}{{\left( {2{\rm{ mol AgN}}{{\rm{O}}_3}} \right)}} = 0.198{\rm{ mol AgCl}}[/tex]

[tex]\begin{array}{l}\\{\rm{Moles}} = \frac{{{\rm{Mass}}}}{{{\rm{Molar mass}}}}\\\\0.198{\rm{ mol}} = \frac{{{\rm{Mass}}}}{{143{\rm{ g/mol}}}}\\\\{\rm{Mass}} = \left( {0.198{\rm{ mol}}} \right)\left( {143{\rm{ g/mol}}} \right)\\\\{\rm{ = 28}}{\rm{.3 g}}\\\end{array}[/tex]

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Answer:

Average speed: approximately [tex]76.9\; {\rm m\cdot s^{-1}}[/tex].

Average velocity: approximately [tex]38.5\; {\rm m \cdot s^{-1}}[/tex] (to the north.)

Explanation:

Consider an object that travelled along a certain path. Distance travelled would be equal to the length of the entire path.

In contrast, the magnitude of displacement is equal to distance between where the object started and where it stopped.

In this question, the path George took required him to travel [tex]750\; {\rm m} + 250\; {\rm m} = 1000\; {\rm m}[/tex] in total. Hence, the distance George travelled would be [tex]1000\; {\rm m}[/tex]. However, since George stopped at a point [tex](750\; {\rm m} - 250\; {\rm m}) = 500\; {\rm m}[/tex] to the north of where he started, his displacement would be only [tex]500\; {\rm m}[/tex] to the north.

Divide total distance by total time to find the average speed.

Divide total displacement by total time to find average velocity.

The total time of travel in this question is [tex]13\; {\rm s}[/tex].. Therefore:

[tex]\begin{aligned}\text{average speed} &= \frac{\text{total distance}}{\text{total time}} \\ &= \frac{1000\; {\rm m}}{13\; {\rm s}} \\ &\approx 76.9\; {\rm m\cdot s^{-1}}\end{aligned}[/tex].

[tex]\begin{aligned}\text{average velocity} &= \frac{\text{total displacement}}{\text{total time}} \\ &= \frac{500\; {\rm m}}{13\; {\rm s}} && \genfrac{}{}{0px}{}{(\text{to the north})}{}\\ &\approx 38.5\; {\rm m\cdot s^{-1}} && (\text{to the north})\end{aligned}[/tex].

When a body moves in a simple harmonic motion, its acceleration at the ends of its path is: zero. So, the correct option is (a).

Simple harmonic motion is the motion of a particle moving in a straight line with an acceleration that is always directed towards a fixed point on the line and whose magnitude is proportional to the distance from the fixed point.

There is no restoring force once the mass has reached equilibrium. Therefore, there is no acceleration, but the mass is travelling at its fastest rate. The mass will continue past the equilibrium position due to its inertia, stretching the string.

Therefore, when a body moves in a simple harmonic motion, its acceleration at the ends of its path is: zero. So, the correct option is (a).

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dimension = 30.0 m ✕ 15.0 m ✕ 5.0 m.

density = 1.20 kg/m3

(a)volume = lenght * breadth * height

      = 30 * 15 * 5

      = 2250 metre cube = 2.25 cubic meter

(b)   mass of air = density * volume

        mass of air = 1.2 * 2250

mass of air = 2700kg

weight  = mass * 9.8

             = 2700 * 9.8

             = 26,460 N

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