14 Explain How do you think the three-story-high ripple marks shown here were formed?
1 answer:
You might be interested in
1) a) attract
The magnetic force between two magnetic poles is attractive for two unlike poles and repulsive for two like poles. Therefore we have:
1- For two north poles, the force between them is repulsive
2- For two south poles, the force between them is repulsive
3- For a north pole and a south pole, the force between them is attractive
In this problem, we are in the situation described in 3), so the force between the poles is attractive.
2) a) motion of electrons
While electric fields are produced by static electric charges, magnetic fields are produced by charges in motion (currents). In particular, a current in a wire (where a current is simply the motion of electrons inside the wire) produces a magnetic field whose intensity is
where
I is the current in the wire
r is the radial distance from the wire
And the direction of the field lines are such that the field form concentric circles around the wire.
Answer:
The elevator must be <u>accelerating upward</u> as the net force acting is upward.
Explanation:
Given:
Original weight of the student,
Reading on the spring scale is the normal reaction by the scale on the student and is given as,
The normal reaction acts in the upward direction while the weight of the student acts vertically downward.
Now, the magnitude of the normal reaction is greater than the magnitude of the weight. Therefore, the net force acting on the student is given as:
Therefore, the net force is acting vertically upward.
Now, as per Newton's second law, the direction of the net acceleration acting on a body is the same as the direction of the net force acting on it.
Thus, the elevator must be accelerating upward as the net force acting is upward.