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An indestructible bullet 2.00cm long is fired straight through a board that is 10.0cm thick. The bullet strikes the board with a speed of 470 m/s and emerges with a speed of 270 m/s. (To simplify, assume that the bullet accelerates only while the front tip is in contact with the wood.) a). What is the average acceleration of the bullet through the board? ____m/s^2b). What is the total time that the bullet is in contact with the board? (Enter the total time for the bullet to completely emerge from the board.) _s
c.) What thickness of board (calculated 0.1 cm) would it take to stop the bullet, assuming that the acceleration through all boards is the same? ____cm

Answers

Answer 1

Answer:

Answer:

a) $a=-7.4* 10^(-5)\ m/s^2$

b) $t=0.27* 10^(-3)\ s$

c)s=14.92 cm

Explanation:

Given that

u= 470 m/s

v = 270 m/s

s= 10 cm

We know that

$v^2=u^2+2as$

$270^2=470^2+2* a* 0.1$

$a=-7.4* 10^(-5)\ m/s^2$

v= u + a t

$270=470-7.4* 10^(-5)* t$

$t=0.27* 10^(-3)\ s$

To stop the bullet it means that the final velocity will be zero.

$v^2=u^2+2as$

$0^2=470^2-2* 7.4* 10^(-5) * s$

s=14.92 cm

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Suppose that you run along three different paths from location A tolocation B. Along which path(s) would your distance traveled be different than your displacement
(Question 2) please help

Answers

Answer:

Path 3 and Path 1

Explanation:

Along Path1andPath3, the distance travelled will be different than the displacement.

In Path1 and Path3 the distance travelled will be more than the displacement. Whereas, in Path2, the displacement will be as same as the distance travelled because in path 2, the distance travelled itself is the shortest distance from initial point ( A ) to final point ( B ).

But, inPath1 and Path3, the total distance travelled isn't the shortest distance from initial point ( A ) to final point ( B ), hene displacement and distance travelled will be different.

$\rule{200}2$

Along Path 1 and path 3 your distance traveled be different than your displacement.

Distance is the total length of the path traveled by an object. It is a scalar quantity, meaning it has only magnitude and no direction.

Displacement is the change in the object's position from its initial to its final position. It is a vector quantity, meaning it has both magnitude and direction.

For example, if an object moves in a circle, the distance traveled will be equal to the circumference of the circle, but the displacement will be zero, since the object returns to its initial position.

Another example is if an object moves back and forth along a straight line, the distance traveled will be twice the length of the line, but the displacement will be zero, since the object returns to its initial position.

In general, the distance traveled will always be greater than or equal to the displacement. This is because the distance traveled includes all of the path that the object takes, while the displacement only includes the change in the object's position.

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In a physics laboratory experiment, a coil with 170 turns enclosing an area of 10.9 cm2 is rotated during the time interval 3.50×10−2 s from a position in which its plane is perpendicular to Earth's magnetic field to one in which its plane is parallel to the field. The magnitude of Earth's magnetic field at the lab location is 5.60×10−5 T. What is the total magnitude of the magnetic flux (initial) through the coil before it is rotated?

Answers

$N= 170 turns\nA=10.9cm^2\nt=3.5*10^(-2)s \n\B = 5.6*10^(-5)T$

The Magnetic flow $\Phi_(initial)$ is given by the formula,

$\Phi_(Initial)=BAsin\theta$

Replacing the values

$\Phi_(Initial) =(5.6*10^(-5))(10.9)((10^(-4)m^2)/(1cm^2)) sin90\°$

$\Phi_(Initial) =6.104*10^(-7) Wb$

A young man walks daily through a gridded city section to visit his girlfriend, who lives m blocks East and nblocks North of where the young man resides. Because the young man is anxious to see his girlfriend, his route to her never doubles back—he always approaches her location. In terms of m and n, how many different routes are there for the young man to take?

Answers

Answer:

The man ate eggs.

Explanation:

He should brush his teeth before seeing his girlfriend.

(a) Is the velocity of car A greater than, less than, or the same as thevelocity of car B?
(b) Is the initial position of car A greater than, less than, or equal to the
initial position of car B?
(c) In the time period from t = 0 tot = 1 s, is car A ahead of car B,
behind car B, or at the same position as car B?

Answers

a. ) Is the velocity of car A less than the velocity of car B b. the initial position of car A greater than the initial position of car B c. ahead In the time period from t = 0 tot = 1 s, is car A ahead of car B?.

what is velocity ?

Velocity is the parameter which is different from speed, can be defined as the rate at which the position of the object is changed with respect to time, it is basically speeding the object in a specific direction in a specific rate.

Velocity is a vector quantity which shows both magnitude and direction and The SI unit of velocity is meter per second (ms-1). If there is a change in magnitude or the direction of velocity of a body, then it is said to be accelerating.

Finding the final velocity is simple but few calculations and basic conceptual knowledge are needed.

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Answer:

a. less than, b. greater than, c. ahead

Explanation:

What does a planet need in order to retain an atmosphere? How does an atmosphere affect the surface of a planet and the ability of life to exist?

Answers

Answer:

Explained

Explanation:

In order to retain atmosphere a planet needs to have gravity. A gravity sufficient enough to create a dense atmosphere around it, so that it can retain heat coming from sun. Mars has shallow atmosphere as its gravity is only 40% of the Earth's gravity. Venus is somewhat similar to Earth but due to green house effect its temperature is very high. Atmosphere has a huge impact on the planets ability to sustain life. Presence of certain kind gases make the atmosphere poisnous for life. The atmosphere should be such that it allows water to remain in liquid form and maintain an optimum temperature suitable for life.

24-gauge copper wire has a diameter of 0.51 mm. The speaker is located exactly 4.27 m away from the amplifier. What is the minimum resistance of the connecting speaker wire at 20°C? Hint: How many wires are required to connect a speaker!Compare the resistance of the wire to the resistance of the speaker (Rsp = 8 capital omega)

Answers

Answer:

R = 8.94 10⁻² Ω/m, R_sp / R_total = 44.8

Explanation:

The resistance of a metal cable is

R = ρ L / A

The area of a circle is

A = π R²

The resistivity of copper is

ρ = 1.71 10⁻⁸ ohm / m

Let's calculate

R = 1.71 10⁻⁸ 4.27 / (π (0.51 10⁻³)²)

R = 8.94 10⁻² Ω/m

Each bugle needs two wire, phase and ground

The total wire resistance is

R_total = 2 R

R_total = 17.87 10⁻² Ω

Let's look for the relationship between the resistance of the bugle and the wire

R_sp / R_total = 8 / 17.87 10⁻²

R_sp / R_total = 44.8

Final answer:

The resistance of the speaker wire can be calculated using the formula for the resistance of a wire, taking into account the resistivity of copper, the length and thickness of the wire, and whether a single or pair of wires is used.

Explanation:

The question is asking you to find the minimum resistance of a copper wire given its diameter and length, plus the resistance of the speaker it's connected to. Resistance of a wire is calculated using the formula R=ρL/A, where R is the resistance, ρ (rho) is the resistivity of the material (in this case, copper), L is the length of the wire, and A is the cross-sectional area of the wire.

First, you need to find the area of the 0.51 mm diameter wire. The area (A) of a wire is given by the formula π(d/2)^2 where d is the diameter of the wire. After calculating the area, use the formula R=ρL/A to calculate the resistance. For copper wire at 20°C, ρ is approximately 1.68 × 10^-8 Ω·m. Substituting these values into the formula will give you the resistance of the wire in ohms.

Note: you may need to consider whether you have just a single wire or a pair, since two wires are typically required to connect a speaker. If a pair is used, each wire will carry half the current, which affects the total resistance.

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