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Which of the following statements are true concerning the creation of magnetic fields? Check all that apply. Check all that appl

anzhelika [568]

Answer:

A permanent magnet creates a magnetic field at all points in the surrounding region.

An electric current in a conductor creates a magnetic field at all points in the surrounding region.

A moving electric charge creates a magnetic field at all points in the surrounding region.

Explanation:

Magnet field is a region around the magnet in which the magnetic force can be experienced. A magnet has two poles: North pole and South pole. A Magnetic field originates from north pole and ends at south pole.

Magnets are of two types: Permanent magnet and temporary magnet.

A moving charge produces magnetic field. A stationary charge can not produce a magnetic field.

The rate of flowing charge constitutes an electric current. If the cardboard is placed around the current carrying conductor and the iron fillings spread around the cardboard then the iron nails get stick to it. It means that a current carrying conductor creates a magnetic field around it.

Therefore, the true statements from the given statements are as follows;

A permanent magnet creates a magnetic field at all points in the surrounding region.

An electric current in a conductor creates a magnetic field at all points in the surrounding region.

A moving electric charge creates a magnetic field at all points in the surrounding region.

8 0

3 years ago

A 90 kg ice skater moving at 12.0 m/s on the ice encounters a region of roughed up ice with a coefficient of kinetic friction of

balandron [24]

Answer:

The skater covers a distance of <u>15 m</u> before stopping.

Explanation:

Let the distance traveled before stopping be 'd' m.

Given:

Mass of the skater (m) = 90 kg

Initial velocity of the skater (u) = 12.0 m/s

Final velocity of the skater (v) = 0 m/s (Stops finally)

Coefficient of kinetic friction (μ) = 0.490

Acceleration due to gravity (g) = 9.8 m/s²

Now, we know that, from work-energy theorem, the work done by the net force on a body is equal to the change in its kinetic energy.

Here, the net force acting on the skater is only frictional force which acts in the direction opposite to motion.

Frictional force is given as:

$f=\mu N$

Where, 'N' is the normal force acting on the skater. As there is no vertical motion, $N=mg$

∴ $f=\mu mg=0.490\times 90\times 9.8=432.18\ N$

Now, work done by friction is a negative work as friction and displacement are in opposite direction and is given as:

$W=-fd=-432.18d$

Now, change in kinetic energy is given as:

$\Delta K=\frac{1}{2}m(v^2-u^2)\\\\\Delta K=\frac{1}{2}\times 90(0-12^2)\\\\\Delta K=45\times (-144)=-6480\ J$

Therefore, from work-energy theorem,

$W=\Delta K\\\\-432.18d=6480\\\\d=\frac{6480}{432.18}\\\\d=14.99\approx 15\ m$

Hence, the skater covers a distance of 15 m before stopping.

7 0

3 years ago

In the diagram, the wavelength is shown by :

MAXImum [283]

Answer:

i think the anwer is C

Explanation:

6 0

3 years ago

Okay! Last question was a warm-up question. And now to get your brain thinking some more, how about another one?:

den301095 [7]

The correct answer is a fishhook

5 0

2 years ago

the space shuttle used three parachutes to land in the image at the start of the project. Why did the space shuttle engineers us

iragen [17]

Answer:

Sep 9, 2008 - Image above: In the Parachute Refurbishment Facility at NASA's ... His parachute, when opened, had a canopy that resembled a huge umbrella. ... Space Center used mainly to process space shuttle parachutes, United Space ... Hillebrandt also is lead engineer for the Constellation Program's Ares 1 rocket ...

Explanation:

Sep 9, 2008 - Image above: In the Parachute Refurbishment Facility at NASA's ... His parachute, when opened, had a canopy that resembled a huge umbrella. ... Space Center used mainly to process space shuttle parachutes, United Space ... Hillebrandt also is lead engineer for the Constellation Program's Ares 1 rocket ...

6 0

2 years ago