U1=20 m/s turn it to km/h

An object with total mass mtotal = 14.6 kg is sitting at rest when it explodes into three pieces. One piece with mass m1 = 4.9 k

zheka24 [161]

Answer: 1) 0. 2) 4.2 Kg. 3) 15.4 m/s 4) 12.9 m/s 5) 0. 6) 3.62 KJ.

Explanation:

1) Assuming that no external forces act during the collision, total momentum must be conserved. As initially the total mass was at rest, so initial momentum is zero, final momentum of all the system must be 0 also.

2) After the explosion, as mass must be conserved also, the sum of the masses of the three pieces must be equal to the original total mass, so we can write the following:

m₁ + m₂ + m₃ = M = 14.6 Kg = 4.9 Kg + 5.5 Kg + m₃

Solving for m₃, we have:

m₃ = 14.6 Kg - 4.9 Kg -5.5 Kg = 4.2 Kg.

3) and 4)

As momentum is a vector, if it is magnitude must be 0, this means that all his components must be 0 too.

So, we can write two equations, one for the x-component, and other for the y-component, as follows:

pₓ = m₁. v₁ₓ + m₂.v₂ₓ + m₃.v₃ₓ = 0

py = m₁.v₁y + m₂. v₂y + m₃. v₃y =0

Replacing by the values, and solving for v₃ₓ and v₃y, we get:

v₃ₓ = 15.4 m/s

v₃y = 12.9 m/s

v = √(15.4)²+(12.9)² = 20.1 m/s

5) As the center of mass must move as if all the mass were concentrated in this point, and we know that the total momentum must be 0, this tells us that the magnitude of the velocity of the center of mass must be 0 too.

6) As initial kinetic energy is 0, as the mass was at rest, the increase in the kinetic energy is obtained simply adding the kinetic energy of every piece of mass gained after explosion, as follows:

K = K₁ + K₂ + K₃ = 1/2 (m₁ . v₁² + m₂.v₂² + m₃.v₃²)

Replacing by the values, we get:

K= 3.62 KJ

4 0

3 years ago

1. Current is usually the flow of

kolbaska11 [484]

Answer:

1. Current is usually the flow of <u>electrons</u>.

Explanation:

The flow of charges through a wire or conductor is called electric current.

7 0

2 years ago

Read 2 more answers

_______ measures an object's change in position per unit time.

Deffense [45]

I believe your answer should be C. Speed.

6 0

3 years ago

Read 2 more answers

An object has a weight of 9 n when it is in air and 7.2 n when it is submerged into water. what is the specific gravity of the o

White raven [17]

The specific gravity of the object’s material is 5.09.

<h3>To calculate the specific gravity of the object:</h3>

Weight difference = 9 - 7.2 = 1.8 N = Buoyant force of water

Buoyant Force in water(Fb) = density of water x g x volume of the body(Vb)

1.8 = 1000 x 9.81 x Vb

Vb = 1.8/9810 cubic meter

Now, in the air;

Weight of body = mg = 9 N

Mass of body,m = 9/9.81 Kg

So,

Density of body = m/ Vb

= 9/9.81 ÷ 1.8/9810

= 5094.44 kg per cubic meter

The specific gravity of body = density of body ÷ density of water

= 5094.44 ÷ 1000

= 5.09

Therefore, Specific gravity of body = 5.09

Learn more about Specific gravity here:

brainly.com/question/13258933

#SPJ4

6 0

1 year ago

A length of wire is cut into five equal pieces. the five pieces are then connected in parallel, with the resulting resistance be

ycow [4]

The equivalent resistance of resistors connected in parallel is
$\frac{1}{R_{eq}} = \frac{1}{R_1} + \frac{1}{R_2} + ...$
In our problem, we have 5 identical resistor of resistance $R$ , so their equivalent resistance is
$\frac{1}{R_{eq}} = 5 (\frac{1}{R} )$
The problem also says that the equivalent resistance is $R_{eq}= 17 \Omega$ , so we can find the resistance R of each piece of wire:
$R=5 R_{eq} = 5 \cdot 17 \Omega = 85 \Omega$

In the initial wire, it's like the 5 pieces are connected in series, so the equivalent resistance of the wire is just the sum of the resistances of the 5 pieces:
$R_{wire} = 5 R = 5 \cdot 85 \Omega = 425 \Omega$

6 0

3 years ago