Answer:
The wheelbarrow's wheel and axle help the wheelbarrow to move without friction thus making it easier to push or pull. That's why it will be easier to lift a load in wheel barrow of the load is transferred towards the wheel.
All the statements can be used to explain about Earth's magnetic field.
Earth's magnetic field is almost same to that of the bar magnet. The magnetic field of the earth occurs from its core. It has an inner core which is solid in nature. in the outer core, there is a motion of the liquid due to heat flow from the inner core to the core mantle boundary which proves that the outer core is liquid and moving. The Earth's core consists of iron and nickel as the Eddy currents in the iron and nickel liquid helps generating the Earth's magnetic field.
Hence, all the three statements are true and can be used to explain the Earth's magnetic field.
Answer:
a) Yes
b) No
Explanation:
In the first case, part a, yes we can say for certainty that cylinderical symmetry holds. Why so? You may ask. This is because from the question, we are told that the length of the rod is 300 cm. And this said length is longer than the distance to the point from the center of the rod, which is 5 cm.
In the second half of the question, I beg to disagree that cylindrical symmetry holds. Again, you may ask why, this is because the length of the rod in this case, is having the same order of magnitude as the distance to the center of the rod. Thus, it is not symmetrical.
The magnetic force on a current-carrying wire due to a magnetic field is given by

where
I is the current
L the wire length
B the magnetic field strength
In our problem, L=1.0 m,

and

, so we can re-arrange the formula to find the current in the wire:
A plane flying initially at 100 m/s uses an acceleration of 5 m/s² to reach a velocity of 150 m/s in 10 seconds.
<h3>What is acceleration?</h3>
Acceleration is the change in velocity over time.
A plane is flying initially at 100 m/s (u) and it accelerates to 150 m/s (v) in 10 s (t). We can calculate its acceleration using the following expression.
a = v - u / t = (150 m/s - 100 m/s) / 10 s = 5 m/s²
A plane flying initially at 100 m/s uses an acceleration of 5 m/s² to reach a velocity of 150 m/s in 10 seconds.
Learn more about acceleration here: brainly.com/question/14344386
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