Answer:
<h2>20 kg</h2>
Explanation:
The mass of the rock can be found by using the formula

f is the force
a is the acceleration
From the question we have

We have the final answer as
<h3>20 kg</h3>
Hope this helps you
The property which leads to the formation of echoes is reflection of sound. When a sound is repeatedly reflected and if minimum distance between sound sources and reflecting surface is more than 17.2 m, then we hear echos
Answer:

Explanation:
The force on this segment is given by:

In the axis z'


So the force is zero in the axis z' because the normal is in the same axis of the magnetic field
In the axis x'



