In general, which tends to be youngest on our planet, ocean crust or continental crust? Explain.

Which statement describes friction?

Vaselesa [24]

Answer:

include the statements pls so i can choose wich one it is and tell you

Explanation:

5 0

3 years ago

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In a jet engine, _________________ is sucked into the front of a compressor, where _____________ is injected into the high press

Kay [80]

The answers are; air, fuel, back, forward

The jet engine utilizes the principle that for every action force there is an equal reaction force in the opposite direction. When the exhaust from the combustion in the engine is ejected with great force backwards, the reaction force pushes the plane forward with an equivalent force.

4 0

3 years ago

A 56-kg skater initially at rest throws a 5.0-kg medicine ball horizontally to the left. Suppose the ball is accelerated through

aniked [119]

Answer:

$a_2=24.5\ \text{m/s}^2$ towards right

$a_1=2.1875\ \text{m/s}^2$ towards left

Explanation:

$m_1$ = Mass of skater = 56 kg

$m_2$ = Mass of ball = 5 kg

v = Final velocity of ball = 7 m/s

u = Initial velocity of ball = 0

s = Distance the ball moved in the hand of the skater = 1 m

Moving left is considered and moving right is considered positive.

From kinematic equations of motion we have

$v^2-u^2=2as\\\Rightarrow a=\dfrac{v^2-u^2}{2s}\\\Rightarrow a=\dfrac{7^2-0^2}{2\times 1}\\\Rightarrow a=24.5\ \text{m/s}^2$

So, the ball will move towards right with a magnitude of acceleration $a_2=24.5\ \text{m/s}^2$ .

The force on the ball will be

$F_2=m_2a_2\\\Rightarrow F_2=5\times 24.5\\\Rightarrow F_2=122.5\ \text{N}$

The force on the ball is $122.5\ \text{N}$

The reaction force on the skater will be equal to the force on the ball but will have opposite direction.

$-F_1=F_2\\\Rightarrow -m_1a_1=F_2\\\Rightarrow a_1=-\dfrac{122.5}{56}\\\Rightarrow a_1=-2.1875\ \text{m/s}^2$

So, the skater will move towards left with a magnitude of acceleration $2.1875\ \text{m/s}^2$

4 0

3 years ago

An object from which neither matter nor light can escape is called a _________.

vichka [17]

The correct answer is a blackhole.

A blackhole is the only object in which nothing, not even light can escape.

Hope this helps!

4 0

4 years ago

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In lecture, Dr. Selby used atmospheric air pressure to crush a can, by sucking the air out of it. (a) Calculate how many Newtons

Ahat [919]

Answer:

a) F1 = 1999.8 N , F2 = 4545 N , F3 = 2778 N , c) the cans do not collapse because the pressure is applied on both sides

Explanation:

Let's use the pressure equation

P = F / A

Suppose we have atmospheric pressure 1.01 10⁵ Pa

Let's calculate the area of the can that is a parallelepiped

Length L = 25 cm

width a = 18 cm

high h = 11 cm

Side area A = h a

A = 11 18

A1 = 198 10⁻⁴ m²

Lid area

A2 = L a

A2 = 25 18

A2 = 450 10⁻⁴ m²

Other side area

A3 = L h

A3 = 25 11

A3 = 275 10⁻⁴ m²

Now let's calculate the force on these sides

Side 1

F1 = P * A1

F1 = 1.01 10⁵ 198 10⁻⁴

F1 = 1999.8 N

Side 2

F2 = P A2

F2 = 1.01 10⁵ 450 10⁻⁴

F2 = 4545 N

Side 3

F3 P A3

F3 = 1.01 10⁵ 275 10⁻⁴

F3 = 2778 N

We see that the force is greater on side 2 which is where the can should collapse

b) To compare the previous forces we must use the concept of density, in general the cans are made of aluminum that has a density of 2700 kg / m3

d = m / V

m = d * V

V = L a h

V = 0.25 0.18 0.11

V = 0.00495 m3

m = 2700 0.00495

m = 13.4 kg

This is the maximum weight, because much of the volume we calculate is air that has a much lower density

W = 13.4 * 9.8

W = 131.3 N

Let's make the comparison by saying the two magnitudes

Side 1

F1 / W = 1999.8 / 131.3

F1 / W = 15.2

Side 2

F2 / W = 4545 / 131.3

F2 / W = 34.6

Side 3

F3 / W = 2778 / 131.3

F3 / W = 21.2

c) the cans do not collapse because the pressure is applied on both sides: outside and inside, so the net force is zero on each side.

7 0

4 years ago