Physics, 30.10.2021 07:30 manman71

What do you think causes magnets to stick to a refrigerator? Why do other objects fall to the floor when placed in the same location?

Answers: 1

Show answers

Answers

# 1: Permanent magnets will attract any ferromagnetic material that is not already magnetized for repulsion. There is an interesting reason for this that surprisingly is seldom taught in science courses that include magnetism as a subject. In these course students are usually simply told that with magnetism like poles repel and opposite poles attract. Since any refrigerator with ferromagnetic surfaces is not likely to be magnetically polarized at first, this doesn’t explain the attraction in this care or in most others. Ferromagnetic materials contain usually microscopic regions called “magnetic domains:” These are regions that have net magnetization. They are like tiny permanent magnets. Usually these domains are randomly oriented magnetically so that their overall magnetic effects almost completely cancel outside of whatever object they make up. Bringing a permanent magnet near such an object causes the domains to change. Some grow in size while others shrink, and there can be small rotations of the magnetic orientations. The domains that grow are the ones with magnetic polarity opposite to that of the permanent magnet that is inducing the effects. This results in attraction. Also any rotations of domains are such as to produce attraction. To simplify, the permanent magnet temporarily causes the nearer parts of the refrigerator surface to become magnetically polarized so that it acts like a magnet with the opposite pole closest to the nearest pole of the permanent magnet. Then opposite magnetic poles attract.

# 2: Gravity. The most remarkable and unexpected fact about falling objects is that, if air resistance and friction are negligible, then in a given location all objects fall toward the center of Earth with the same constant acceleration, independent of their mass.

Answer from: Quest

multiple allele inheritance is traits controlled by more than 2 alleles (ex: pigeons having 3 alleles of one gene govern their feather color).

Answer from: Quest

m₁v₁ + m₂v₂ = (m₁ + m₂)vmomentum is conserved.the left-hand side of the equation represents the momentum in the system before the collision.the right-hand side represents the momentum in the system after the collisionm₁ and v₁ represents the mass and the velocity of the physics blockm₂ and v₂ represents the mass and velocity of the ball of puttyv represents the final velocity of the combined mass.the question states the two masses stick together. they combined mass has its own velocity with the body mass the sum of the two objects' massestheir combined momentum is (m₁ + m₂)vto find the magitude of (m₁ + m₂)v, we need to add the vectors on the left-hand side of the equation: m₁v₁ + m₂v₂.note the diagram. i have positioned the vectors in accordance with their directions.the magnitude of the resultant can be calculated using the pythagorean theorem since this is a right triangle situation (north and west are perpendicular)|(m₁ + m₂)v| = √[ (m₁v₁)² + (m₂v₂)² ]|(m₁ + m₂)v| = √[ (1.5kg·8.0m/s)² + (0.40kg·20m/s)² ]|(m₁ + m₂)v| = 14.4 kg m/sfor two significant figures (assuming that 20m/s is two), this rounds to 14 kg m/s

Another question on Physics

Physics, 21.06.2019 18:30

Three archers each fire four arrows at a target. joe’s four arrows hit at points 10 cm above, 10 cm below, 10 cm to the left, and 10 cm to the right of the center of the target. all four of moe’s arrows hit within 1 cm of a point 20 cm from the center, and flo’s four arrows hit within 1 cm of the center. the contest judge says that one of the archers is precise but not accurate, another archer is accurate but not precise, and the third archer is both accurate and precise. which description applies to which archer? explain

Answers: 2

Answer

Physics, 22.06.2019 02:30

Agas contained within a piston-cylinder assembly undergoes three processes in series: process 12: compression with pv= constant from 1 bar and 1 liter to 4 bar. process 23: constant pressure expansion to 1 liter. process 31: constant volume calculate the pressure and volume at each state, and sketch the processes on a p-vdiagram labeled with pressure and volume values at each numbered stat

Answers: 2

Answer

Physics, 22.06.2019 09:30

How would a small bar magnet be oriented when placed at position x?

Answers: 2

Answer

Physics, 22.06.2019 11:30

1. a camcorder has a power rating of 19 watts. if the output voltage from its battery is 7 volts, what current does it use?answer units 2. a 1.5m wire carries a 6 a current when a potential difference of 57 v is applied. what is the resistance of the wire? yourunits 3. a clothes dryer uses about 2 amps of current from a 240 volt line. how much power does it use? yourunits 4.

Answers: 1

Answer

You know the right answer?

What do you think causes magnets to stick to a refrigerator? Why do other objects fall to the floor...

Questions