I would say unlimited polarity because the compass’s needle is always attracted to Earth’s north pole.
Good luck to you!
Answer:
Should place the current perpendicular to the magnetic field
Explanation:
The magnetic force exerted on a current-carrying wire is given by

where
I is the current in the wire
L is the length of the wire
B is the magnetic field
is the angle between the direction of the wire and the magnetic field
As we see from the formula, the magnetic force is maximum when

which means

So, when the current in the wire and the magnetic field are perpendicular to each other.
Answer:
(A) V = 9.89m/s
(B) U = -2.50m/s
(C) ΔK.E = –377047J
(D) ΔK.E = –257750J
Explanation:
The full solution can be found in the attachment below. The east has been chosen as the direction for positivity.
This problem involves the principle of momentum conservation. This principle states that the total momentum before collision is equal to the total momentum after collision. This problem is an inelastic kind of collision for which the momentum is conserved but the kinetic energy is not. The kinetic energy after collision is always lesser than that before collision. The balance is converted into heat by friction, and also sound energy.
See attachment below for full solution.
Answer:
The small pebble
Explanation:
Since the potential energy, P.E lost equals kinetic energy, K.E gained,
P.E = K.E
P.E = mgh = K.E
So, K.E = mgh where g = acceleration due to gravity and h = height of drop
Since h and g are constant
K.E ∝ m
So, the kinetic energy of the object is directly proportional to its mass. Thus, the object with the smaller mass has the lesser kinetic energy.
Since the object with the smaller mass is the small pebble, so the small pebble would have less kinetic energy as it crashes on the road at the bottom of the mountain.