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Mandarinka [93]

3 years ago

6

a) A bus of mass 760 kg requires 120 m to reach certain velocity value Vf. Ignore friction and drag forces and assume the bus en

gine exerts a constant forward force F. When the bus is towing a 330-kg small car, how long distance needed to reach same Vf? b) If the Vf of the bus is 28 m/s, what is the tension in the tow cable between bus and small car?

1 answer:

zmey [24]3 years ago

7 0

Answer:

Given : A bus of mass 760 kg requires 120 m to reach certain velocity value Vf.

the bus engine exerts a constant forward force F.

To Find : When the bus is towing a 330-kg small car, how long distance needed to reach same Vf?

Solution:

V² - U² = 2aS

V = Vf

U = 0

S = 120 m

=> Vf² - 0 = 2a(120)

=> Vf² = 240a

m = 760 kg

Force = F

F = ma

=> F =760 a

=> a = F/760

Vf² = 240F/760

Case 2 :When the bus is towing a 330-kg small car,

m = 760 + 330 = 1090 kg

a = F/1090

Vf² = 2aS

=> 240F/760 = 2 (F/1090) S

=> S = 120 x 1090 /760

=> S = 172.1 m

172.1 m distance needed to reach same Vf

Explanation:

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shutvik [7]

Answer:

4.0 m/s

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4 0

3 years ago

a car company wants to ensure its newest model can stop in 50 m when traveling at 30 m/s (which is about 108 km/h). if we assume

Brut [27]

A decrease in velocity is referred to as deceleration. If car is moving at 30 m/s and stop in 50 m .The value of deceleration is 11.56 ms−2.

<h3>How to calculate deceleration ?</h3>

While acceleration is motion in which an object's speed varies every second, deceleration is motion that causes an object to slow down.

We are aware that acceleration refers to an object's rate of increase in speed, and deceleration refers to an object's rate of decrease in speed. For instance, when we apply the brakes while driving, we benefit from the vehicle's ability to decelerate and slow down.

The Deceleration Formula is the final velocity minus the initial velocity, with a negative sign in the result because the velocity is decreasing, if starting velocity, final velocity, and time taken are given.

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= 11.56

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8 0

1 year ago

Physics B 2020 Unit 3 Test

weqwewe [10]

Answer:

1)

When a charge is in motion in a magnetic field, the charge experiences a force of magnitude

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where here:

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2)

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The density of the field lines at any point tells how strong is the magnetic field at that point.

If we observe the field lines around a magnet, we observe that:

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Therefore, this means that the magnetic field of a magnet is stronger near the North and South Pole.

3)

The right hand rule gives the direction of the force experienced by a charged particle moving in a magnetic field.

It can be applied as follows:

- Direction of index finger = direction of motion of the charge

- Direction of middle finger = direction of magnetic field

- Direction of thumb = direction of the force (for a negative charge, the direction must be reversed)

In this problem:

- Direction of motion = to the right (index finger)

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4)

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$r=\frac{mv}{qB}$

where here we have:

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Substituting, we find:

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5)

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where here:

$q=1.602\cdot 10^{-19}C$ is the charge of the electron

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$m=9.31\cdot 10^{-31} kg$ is the mass of the electron

Substituting, we find:

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6)

When a charged particle moves in a magnetic field, its path has a helical shape, because it is the composition of two motions:

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2- A circular motion in the direction perpendicular to the magnetic field

The second motion is due to the presence of the magnetic force. However, we know that the direction of the magnetic force depends on the sign of the charge: when the sign of the charge is changed, the direction of the force is reversed.

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7)

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$\Delta t$ is the time elapsed

From the formula, we see that the emf is induced in the loop (and so, a current is also induced) only if $\Delta \Phi \neq 0$ , which means only if there is a change in magnetic flux through the loop: this occurs if the magnetic field is changing, or if the area of the loop is changing, or if the angle between the loop and the field is changing.

8)

The flux is calculated as

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So the flux is

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See the last 7 answers in the attached document.

<span class="sg-text sg-text--link sg-text--bold sg-text--link-disabled sg-text--blue-dark"> docx </span>

<span class="sg-text sg-text--link sg-text--bold sg-text--link-disabled sg-text--blue-dark"> pdf </span>

5 0

3 years ago

Some students set up a circuit and decided to measure the voltage at different points around

Fiesta28 [93]

Answer:

V₁ = 6 V , V₂ = V₃ = 3 V

Explanation:

To solve this circuit we must remember that there are two fundamental types of construction in series and parallel.

* a serial circuit there is only one path for current

in this circuit the constant current in the entire circuit and the voltage is the sum of the voltage of each term

* Parallel circuit in this there are two or more paths for the current

in this circuit the voltage is constant and the east is divided between each branch

with these principles let's analyze the proposed circuit

The DC battery is in parallel with resistor R1 and the equivalent of the other branch,

as in a parallel circuit the voltage is constant

V₁ = 6 V

in the other branch (23) it forms a series construction, where the current is constant

6 = iR₂ + iR₃

as they indicate that each resistance has the same value

6 = 2 iR

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3 0

3 years ago

Doss [256]

Answer/Explanation:

The weight of an object is defined as the force that is exerted due to the gravitational force.

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We know that the value of g varies with respect to the location. At the equator, the value of g is less as compared to the poles.

The feature of an object that affects its weight are :

Mass of the object

Location of the object

How much force Earth exerts on the object

4 0

3 years ago