Answer:
<h2>392 J</h2>
Explanation:
The potential energy of a body can be found by using the formula
PE = mgh
where
m is the mass
h is the height
g is the acceleration due to gravity which is 9.8 m/s²
From the question we have
PE = 20 × 9.8 × 2
We have the final answer as
<h3>392 J</h3>
Hope this helps you
Explanation:
Formula for angle subtended at the center of the circular arc is as follows.

where, S = length of the rod
r = radius
Putting the given values into the above formula as follows.

= 
= 
= 
Now, we will calculate the charge density as follows.

= 
= 
Now, at the center of arc we will calculate the electric field as follows.
E = 
= 
= 34.08 N/C
Thus, we can conclude that the magnitude of the electric eld at the center of curvature of the arc is 34.08 N/C.
Answer:
Potential energy =mass* acceleration due to gravity * height
mass*acceleration due to gravity =weight
hence potential energy of the puppy= weight * height
=18*2
=36 joule