A140-g ball containing 4.10 * 108 excess electrons is dropped into a 110-m vertical shaft. at the bottom of the shaft, the ball suddenly enters a uniform horizontal magnetic field that has magnitude 0.300 t and direction from east to west. if air resistance is negligibly small, find the magnitude and direction of the force that this magnetic field exerts on the ball just as it enters the field.

Magnetic force, from north to south.

Explanation:

It is given that,

Mass of the ball, m = 140 g = 0.14 kg

Number of electrons,

Height, h = 110 m

Charge, q = ne

Magnetic field, B = 0.3 T

The potential energy at height of 110 meters is balanced by the kinetic energy as per the law of conservation of energy as :

Magnetic force is given by :

F = q v B

As the direction of magnetic field is from east to west, so from right hand thumb rule the direction of magnetic force is from north to south. Hence, this is the required solution.

the independent variable, the one that is intentionally manipulated, is whether or not the car hits the barrier.

the dependent variable, the one that you measure the response in, is the distance that the washers travel.

answer: the exterior temperature of commercial jet planes as they leave the stratosphere and return to the ground increases steadily.

explanation:

the lower most layer of atmosphere is troposphere which extends from 0 to 12 km above the surface of the earth. the temperature initially decreases as distance is increased from the earth's surface. commercial jets fly in lower part of the stratosphere. the stratosphere extends upto 50 km. the temperature in stratosphere starts rising again due to presence of ozone which traps the uv rays.

thus, when the planes leave the stratosphere and return to the ground, the exterior temperature increases steadily.