<span>Days and nights are equal in length everywhere.(gradpoint)</span>
Answer:
1.48kg
Explanation:
Here,
potential energy (P.E) = 29j
height (h) = 2m
acceleration due to gravity(g) =

mass(m) = ?
we know,
P.E = mgh
or, 29 = m×9.8×2
or, 29/19.6 = m
or,m = 1.48kg
Answer:
1:4
Explanation:
The formula for calculating kinetic energy is:

If the mass is multiplied by 4, then, the kinetic energy must be increased by 4 as well. Since they will be travelling at the same speed when they are at the same point, the relation between KA and KB must be 1:4 or 1/4. Hope this helps!
This problem uses the relationships among current
I, current density
J, and drift speed
vd. We are given the total of electrons that pass through the wire in
t = 3s and the area
A, so we use the following equation to to find
vd, from
J and the known electron density
n,
so:

<span>The current
I is any motion of charge from one region to another, so this is given by:
</span>

The magnitude of the current density is:

Being:

<span>
Finally, for the drift velocity magnitude vd, we find:
</span>
Notice: The current I is very high for this wire. The given values of the variables are a little bit odd