Answer:
10 newtons
Explanation: 10 of the 20 cancels out and the other 10 is force.
Answer:
Given:
Mass of elephant = 5240 kg
The initial speed of the elephant = 4.55 m/s
Mass of the rubber ball, m, = 0.15 kg
Inital speed of the rubber ball, v = 7.81 m/s
On substitution in
=
+ ![[\frac{m_{2}-m_{1}}{m_{1}+m_{2} } ] v_{2f}](https://tex.z-dn.net/?f=%5B%5Cfrac%7Bm_%7B2%7D-m_%7B1%7D%7D%7Bm_%7B1%7D%2Bm_%7B2%7D%20%20%7D%20%5D%20v_%7B2f%7D)
=
+ ![[\frac{0.15_{}-5240_{}}{5240_{}+0.15_{} } ] (7.81_{})](https://tex.z-dn.net/?f=%5B%5Cfrac%7B0.15_%7B%7D-5240_%7B%7D%7D%7B5240_%7B%7D%2B0.15_%7B%7D%20%20%7D%20%5D%20%287.81_%7B%7D%29)
a) The negatıve sign shows that the ball bounces back in the direction opposite to the incident
b) it is clear that the velocity of the ball increases and therefore it is kinetic energy
. The ball gains kinetic energy from the elephant.
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.
Smallerrrrrrrrrrrrrrrrrrrrrrrro