The North Magnetic Pole is the point on the surface of Earth's Northern Hemisphere at which the planet's magnetic field points vertically downwards (in other words, if a magnetic compass needle is allowed to rotate about a horizontal axis, it will point straight down). There is only one location where this occurs, near (but distinct from) the Geographic North Pole and the Geomagnetic North Pole.
Air caught in the ball of foil makes the ball less dense than water
Water because the light is able to enter the water and allow heat to enter faster.
Answer:
Terminal speed, v = 6901.07 m/s
Explanation:
It is given that,
Mass of the horizontal bar, m = 30 g = 0.03 kg
Length of the bar, l = 13 cm = 0.13 m
Magnetic field, 
Resistance, R = 1.2 ohms
We need to find the terminal speed oat which the bar falls. When terminal speed is reached,
Force of gravity = magnetic force
..................(1)
i is the current flowing
l is the length of the rod
Due to the motion in rods, an emf is induced in the coil which is given by :
, v is the speed of the bar


Equation (1) becomes,



v = 6901.07 m/s
So, the terminal speed at which the bar falls is 6901.07 m/s. Hence, this is the required solution.
Answer:
21.7 seconds.
Explanation:
Woman's velocity relative to train (23 m/s - 22.4 m/s) = 0.6 m/s
Distance woman wants to travel = 13m
To find how long she will take to move 13m relative to the train, take the distance she wants to travel divided by her velocity relative to the train.
(13m)/(0.6 m/s) = 21.6667 seconds or 21.7 seconds.
Therefore, it will take the woman 21.7 seconds to move 13m.