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3 years ago

Which statements about Earth’s core help explain Earth’s magnetic field? Check all that apply.

Physics

2 answers:

nalin [4]3 years ago

7 0

The inner core is liquid and moving.

siniylev [52]3 years ago

4 0

Answer:

The inner core is solid.

The outer core is liquid and moving.

Earth’s core is composed of iron and nickel.

Explanation:

Convection currents are produced in the outer liquid core. This motion together with the Earth's rotation creates a system of electrical currents, since it is composed of metals such as iron and nickel. The magnetic fields generated by the electric currents align, creating the Earth's magnetic field. The solid inner core acts as a stabilizer of the magnetic field generated by the liquid outer core.

You might be interested in

What is the name of the force that is a combination of all forces that act on an object?

jarptica [38.1K]

Answer:

If the combination of all the forces acting on an object sums upto be zero, then the net force is known as balanced force.

If the combination of all the forces acting on an object is non-zero, then the net force is said to be unbalanced force. The unbalanced force causes the object change the state of rest or motion.

6 0

3 years ago

A motor running at 2600 rev/min is suddenly switched off and decelerates uniformly to rest after 10 s. Find the angular decelera

Mama L [17]

Angular acceleration = (change in angular speed) / (time for the change)

change in angular speed = (zero - 2,600 RPM) = -2,600 RPM

time for the change = 10 sec

Angular acceleration = -2600 RPM / 10 sec = -260 rev / min-sec

(-260 rev/min-sec) x (1 min / 60 sec) = -(4 1/3) rev / sec²

Since the acceleration is negative, the motor is slowing down.
You might call that a 'deceleration' of (4 1/3) rev/sec² .

The average speed is 1/2(2,600 + 0) = 1,300 rev/min = (21 2/3) rev/sec.

Number of revs = (average speed) x (time) = (21 2/3) x (10sec) = (216 2/3) revs

6 0

3 years ago

In the following figure, if AB ǁ CD, then find the measure of PCD and CPD.

mina [271]

Answer:

$CPD = 80$

$PCD = 44$

Explanation:

Given

$AB || CD$

$BAD = 56$

$CPA = 100$

See attachment

Required

Determine PCD and CPD

First, we need to calculate CPD

Since DPA is a straight line and CPA = 100;

We have that:

$CPA + CPD = 180$ --- angle on a straight theorem

Substitute 100 for CPA

$100 + CPD = 180$

Subtract 100 from both sides

$100-100 + CPD = 180-100$

$CPD = 80$

Next, we calculate PCD

We have that:

$DAB= ADC = 56$ --alternate angle

In triangle PCD

$PCD + CPD + PDC = 180$ --- angles in a triangle

Where

$PDC = ADC = 56$

So, we have:

$PCD +80 + 56 = 180$

$PCD +136 = 180$

Subtract 136 from both sides

$PCD = 180 - 136$

$PCD = 44$

6 0

3 years ago

If we start with 1.000 g of cobalt-60, 0.675 g will remain after 3.00 yr. this means that the of is _____

Tju [1.3M]

Cobalt-60 is undergoing a radioactivity decay.

The formula of the decay is n=N(1/2)∧(T/t).
Where N ⇒ original mass of cobalt
 n ⇒ remaining mass of cobalt after 3 years
T ⇒ decaying period
t ⇒ half-life of cobalt.

So,
0.675 = 1 × 0.5∧(3/t)
log 0.675 = log 0.5∧(3/t)
3/t = log 0.675 ÷log 0.5
3/t= 0.567

t = 3÷0.567
= 5.290626524

the half-life of Cobalt-60 is 5.29 years.

8 0

3 years ago

What is the magnitude of the electric field at a distance of 89 cm from a 27 μC charge, in units of N/C?

GuDViN [60]

Answer:

306500 N/C

Explanation:

The magnitude of an electric field around a single charge is calculated with this equation:

$E(r) = \frac{1}{4 \pi *\epsilon 0} \frac{q}{r^2}$

With ε0 = 8.85*10^-12 C^2/(N*m^2)

Then:

$E(0.89) = \frac{1}{4 \pi *8.85*10^-12} \frac{27*10^-6}{0.89^2}$

E(0.89) = 306500 N/C

3 0

3 years ago