Ask question

Ask question

All categories

3 years ago

12

The high-speed police chase ends at an intersection as a 2,150-kg Ford Explorer (driven by Robin) traveling south at 35 m/s coll

ides with a 18,250-kg garbage truck moving east at 1.55 m/s. The Explorer and the garbage truck entangle together in the middle of the intersection and move as a single object. Determine the post-collision speed two entangled vehicles.

1 answer:

defon3 years ago

4 0

Answer:

The post-collision speed of the two entangled vehicles is 5.08m/s

Explanation:

According to the law of conservation of momentum which states that the sum of momentum of a body before collision is equal to the sum of the collision of the bodies after collision. The bodies moves with the same velovity after collision.

Mathematically, mu + MU = (m+M)v

m and M are the masses of the bodies

u and U are their respective velocities

v is their common velocity

Momentum = mass*velocity

BEFORE COLLISION;

Momentum of Ford Explorer = 2150*35

= 75,250kgm/s

Momentum of the garbage truck = 18, 250 * 1.55

= 28,287.5kgm/s

AFTER COLLISION;

Note that the body will move with the same velocity after collision.

Momentum of the bodies after entangling = (2,150+18,250)v

= 20,400v kgm/s (v is their common velocity)

According to thr law;

75,250+28,287.5 = 20,400v

103,537.5 = 20,400v

v = 103,537.5/20,400

v = 5.08m/s

The post-collision speed of the two entangled vehicles is 5.08m/s

You might be interested in

The British gold sovereign coin is an alloy of gold and copper having a total mass of 7.988 g, and is 22-karat gold 24 x (mass o

matrenka [14]

Answers:

(a) $0.0073kg$

(b) Volume gold: $3.79(10)^{-7}m^{3}$ , Volume cupper: $7.6(10)^{-8}m^{3}$

(c) $17633.554kg/m^{3}$

Explanation:

<h2>(a) Mass of gold </h2><h2 />

We are told the total mass $M$ of the coin, which is an alloy of gold and copper is:

$M=m_{gold}+m_{copper}=7.988g=0.007988kg$ (1)

Where $m_{gold}$ is the mass of gold and $m_{copper}$ is the mass of copper.

In addition we know it is a 22-karat gold and the relation between the number of karats $K$ and mass is:

$K=24\frac{m_{gold}}{M}$ (2)

Finding ${m_{gold}$ :

$m_{gold}=\frac{22}{24}M$ (3)

$m_{gold}=\frac{22}{24}(0.007988kg)$ (4)

$m_{gold}=0.0073kg$ (5) This is the mass of gold in the coin

<h2>(b) Volume of gold and cupper</h2><h2 />

The density $\rho$ of an object is given by:

$\rho=\frac{mass}{volume}$

If we want to find the volume, this expression changes to: $volume=\frac{mass}{\rho}$

For gold, its volume $V_{gold}$ will be a relation between its mass $m_{gold}$ (found in (5)) and its density $\rho_{gold}=19.30g/cm^{3}=19300kg/m^{3}$ :

$V_{gold}=\frac{m_{gold}}{\rho_{gold}}$ (6)

$V_{gold}=\frac{0.0073kg}{19300kg/m^{3}}$ (7)

$V_{gold}=3.79(10)^{-7}m^{3}$ (8) Volume of gold in the coin

For copper, its volume $V_{copper}$ will be a relation between its mass $m_{copper}$ and its density $\rho_{copper}=8.96g/cm^{3}=8960kg/m^{3}$ :

$V_{copper}=\frac{m_{copper}}{\rho_{copper}}$ (9)

The mass of copper can be found by isolating $m_{copper}$ from (1):

$M=m_{gold}+m_{copper}$

$m_{copper}=M-m_{gold}$ (10)

Knowing the mass of gold found in (5):

$m_{copper}=0.007988kg-0.0073kg=0.000688kg$ (11)

Now we can find the volume of copper:

$V_{copper}=\frac{0.000688kg}{8960kg/m^{3}}$ (12)

$V_{copper}=7.6(10)^{-8}m^{3}$ (13) Volume of copper in the coin

<h2>(c) Density of the sovereign coin</h2><h2 />

Remembering density is a relation between mass and volume, in the case of the coin the density $\rho_{coin$ will be a relation between its total mass $M$ and its total volume $V$ :

$\rho_{coin}=\frac{M}{V}$ (14)

Knowing the total volume of the coin is:

$V=V_{gold}+V_{copper}=3.79(10)^{-7}m^{3}+7.6(10)^{-8}m^{3}=4.53(10)^{-7}m^{3}$ (15)

$\rho_{coin}=\frac{0.007988kg}{4.53(10)^{-7}m^{3}}$ (16)

Finally:

$\rho_{coin}=17633.554kg/m^{3}}$ (17) This is the total density of the British sovereign coin

6 0

3 years ago

(NEED HELP PLEASE) A physics student goes to the roof of the school, 24.15 m above the ground, and drops a pumpkin straight down

slavikrds [6]

Answer:

t = 2.2 s

Explanation:

Given that,

Height of the roof, h = 24.15 m

The initial velocity of the pumpkin, u = 0

We need to find the time taken for the pumpkin to hit the ground. Let the time be t. Using second equation of kinematics to find it as follows :

$h=ut+\dfrac{1}{2}at^2$

Here, u = 0 and a = g

$h=\dfrac{1}{2}gt^2\\\\t=\sqrt{\dfrac{2h}{g}} \\\\t=\sqrt{\dfrac{2\times 24.15}{9.8}} \\\\t=2.22\ s$

So, it will take 2.22 s for the pumpkin to hit the ground.

7 0

3 years ago

Why is the same side of the Moon always visible from Earth?

son4ous [18]

Answer:

Explanation:

Answer

The true fact is that C is what happens in outer space. Both rotations take 27.3 days.

A: The exact opposite is true. It does rotate about it's axis.

B: Again this is just plain false. Given the way we observe it, the moon must be rotating around the earth.

D. they don't. 27.3 hours and 24 hours are not the same.

8 0

2 years ago

Which is the correct answer?

Nezavi [6.7K]

Answer:

Point A

Explanation:

The work done by stretching or compressing a spring is given by E=1/2kx²

The potential energy is numerically equal to the work done.

This means that the higher the bigger the value of the extension, x, the higher the energy contained.

In this scenario the modulus of x is considered.

Among the given values of x the modulus of -5 is the largest.

thus it gives the highest value of energy.

7 0

3 years ago

When an oxygen atom forms an ion, it gains two electrons. What is the electrical charge of the oxygen ion?

Mashutka [201]

-2. This is because it is gaining electrons. Electrons are negative. Therefore it is a negative charge.

6 0

3 years ago