What happens when you place two magnets close together.

The man fire a 50-g arrow that moves at an unknown speed. It hits and embeds in a 350-g block that slides on an air track. At th

Natasha_Volkova [10]

Answer:

a) vAix = 80 m/s

b) The assumptions and implications were:

Assume that friction between the block and the surface it rests on does not change the momentum of the system during the collision.

Assume that friction is negligible throughout the process and the system’s internal energy does not change.

Assume all the system’s kinetic energy is converted into elastic potential energy at the end of the process.

If any of the assumptions are invalid then the arrow must have been travelling initially, vAix > 80 m/s

Explanation:

Arrow embeds into block

Take in the first instance the system to be the arrow + block (isolated). Establish reference coordinate system with the +x axis running horizontally in the direction of the arrow’s motion. The initial state (i) is the arrow travelling with velocity vAix and the final state (f) is the arrow embedded in the block. Now, apply the component form of the Generalized Impulse Momentum Equation to this system:

pAi + pBi + JonA + JonB = pAf + pBf

pAix + pBix + Jx = pAfx + pBfx

mA*vAix + mB*vBix + 0 = (mA + mB)*vfx

0.05*vAix + 0 = (0.05 + 0.35)*vfx

vAix = 8*vfx (1)

Arrow embeds into block

Now consider the next phase of motion and take as the system the arrow + block + spring. The initial state (i) is the arrow and block travelling with velocity equivalent to the final velocity from equation 1 (final state velocity in first phase becomes initial velocity in next phase); vix’ = vfx and the final state (f) is the arrow + block brought to rest and the spring compressed an amount, Δx = 0.1 m. Now, apply the Generalized Work Energy Principle to the system

Ei + W = Ef

Ki + Usi + W = Kf + Usf

0.5*(mA + mB)*vix’² = 0.5*k*Δx²

(0.05 + 0.35)*vfx² = 4000*(0.1)²

vfx = √(40/0.4) = 10 m/s

Substituting above back into equation 1:

vAix = 8* 10 m/s = 80 m/s

Arrow embeds into block

The assumptions and implications were:

Assume that friction between the block and the surface it rests on does not change the momentum of the system during the collision.

Assume that friction is negligible throughout the process and the system’s internal energy does not change.

Assume all the system’s kinetic energy is converted into elastic potential energy at the end of the process.

If any of the assumptions are invalid then the arrow must have been travelling initially, vAix > 80 m/s

7 0

3 years ago

A 1500kg car double its speed from 50km/h to 100km/h. By how many times does the kinetic energy from the car's forward motion in

Rashid [163]

Answer:

Explanation:

Inital KE = (1/2) m v^2 = (1/2) * 1500 * 50^2 = 1,875,000 J

Final KE = (1/2) * 1500 * 100^2 = 7,500,000 J

But ,

4 * 1875000 = 7500000

so the KE has increased by 4 times.

8 0

3 years ago

Read 2 more answers

The formula for distance divided by time

azamat

It would be: Speed = Distance / Time

4 0

3 years ago

if the bar and block are too heavy, one of the strings may break. assuming that the two strings are identical, which one will br

DerKrebs [107]

The string that will break first depends on the weight of the block or bar subjected to such string.

According to Hook's law, the force applied to an elastic material is directly proportional to the extension of the material.

F= kx

where;

<em>F is the force applied to the object = weight of the object</em>

For given two identical strings, the string that will break first depends on the mass of the bar and the block.

If the bar is heavier than the block, then the string subjected to the bar will break first.
On the other hand, if the block is heavier than the bar, then the string subjected to the block will break first.

Thus, the string that will break first depends on the weight of the block or bar subjected to such string.

Learn more here:brainly.com/question/4404276

7 0

3 years ago

When completely filled with water, the beaker and its contents have a total mass of 326.75 g. What volume does the beaker hold?

miv72 [106K]

Answer:

0.003060 cm³

Explanation:

Mass of water = m = 326.75 gram

Density of water = ρ = 1.00 g/mL = 1 g/cm³

density = mass / volume

⇒volume = density / mass

⇒volume = 1 / 326.75

⇒Volume = 0.0030604 cm³

∴ Volume held by beaker = 0.0030604 cm³

Here the combined mass of the beaker and water is given so the volume found will be of the beaker as well as the liquid. But, it can be seen that the volume is so small that subtracting the beaker mass would have negligible effect.

6 0

3 years ago

What happens when you place two magnets close together.​

What happens when you place two magnets close together.