The speed 120 km/h is about 25 m/s 33 m/s 42 m/s 50 m/s

A 2.0-kg ball rolls to the right at 3.0 m/s. A 4.0-kg ball rolls to the left at 2.0 m/s . What is the momentum of the system aft

charle [14.2K]

Answer:

Final momentum after a head on collision is -2kgm/s

Explanation:

One ball moves to the right and the other moves opposite and momentum is a vector quantity so that considering the direction

Initial momenta are P₁=2x3=6kgm/s P₂=4x(-2)=-8kgm/s

Final momentum is the vector sum of P(final)= 6-8= -2 kgm/s

4 0

2 years ago

Our city is considering a program to spray insecticide to reduce the number of mosquitoes in the area. Before they do, they want

Anarel [89]

(C) the government agency that regulates these types of chemicals

3 0

3 years ago

Read 2 more answers

Some hypothetical alloy is composed of 12.5 wt% of metal A and 87.5 wt% of metal B. If the densities of metals A and B are 4.27

densk [106]

Answer:

The number of atoms in the unit cell is 2, the crystal structure for the alloy is body centered cubic.

Explanation:

Given that,

Weight of metal A = 12.5%

Weight of metal B = 87.5%

Length of unit cell = 0.395 nm

Density of A = 4.27 g/cm³

Density of B= 6.35 g/cm³

Weight of A = 61.4 g/mol

Weight of B = 125.7 g/mol

We need to calculate the density of the alloy

Using formula of density

$\rho=n\times\dfrac{m}{V_{c}\times N_{A}}$

$n=\dfrac{\rho\timesV_{c}\times N}{m}$ ....(I)

Where, n = number of atoms per unit cells

m = Mass of the alloy

V=Volume of the unit cell

N = Avogadro number

We calculate the density of alloy

$\rho=\dfrac{1}{\dfrac{12.5}{4.27}+\dfrac{87.5}{6.35}}\times100$

$\rho=5.98$

We calculate the mass of the alloy

$m=\dfrac{1}{\dfrac{12.5}{61.4}+\dfrac{87.5}{125.7}}\times100$

$m=111.15$

Put the value into the equation (I)

$n=\dfrac{5.9855\times(0.395\times10^{-9}\times10^{2})^3\times6.023\times10^{23}}{111.15}$

$n=1.99\approx 2\ atoms/cell$

Hence, The number of atoms in the unit cell is 2, the crystal structure for the alloy is body centered cubic.

5 0

3 years ago

How does a arrow represent displacement

Lera25 [3.4K]

Answer:

An arrow represents displacement. Because it's a vector quantity.

Vector quantity= Direction+Magnitude

When an arrow is put above a unit like

acceleration
displacement

it means that it's a vector quantity.

Hope this helps ;) ❤❤❤

4 0

3 years ago

11–8 Consider a heavy car submerged in water in a lake with a flat bottom. The driver’s side door of the car is 1.1 m high and 0

Greeley [361]

Answer:

Explanation:

position of centre of mass of door from surface of water

= 10 + 1.1 / 2

= 10.55 m

Pressure on centre of mass

atmospheric pressure + pressure due to water column

10 ⁵ + hdg

= 10⁵ + 10.55 x 1000 x 9.8

= 2.0339 x 10⁵ Pa

the net force acting on the door (normal to its surface)

= pressure at the centre x area of the door

= .9 x 1.1 x 2.0339 x 10⁵

= 2.01356 x 10⁵ N

pressure centre will be at 10.55 m below the surface.

When the car is filled with air or it is filled with water , in both the cases pressure centre will lie at the centre of the car .

7 0

3 years ago