The nail has become a temporary magnet, while the
bar magnet remains a permanent magnet.
Answer: The direction of an electric current is by convention the direction in which a positive charge would move. Thus, the current in the external circuit is directed away from the positive terminal and toward the negative terminal of the battery. Electrons would actually move through the wires in the opposite direction.
Explanation:
(a) The value of the gravitational acceleration is given by:

where
is the gravitational constant
M is the Earth's mass
is the Earth's radius at the pole
If we use the value for g given by the problem,
, and we rearrange the equation above, we find the value of the Earth's mass:

(b) The value we found for the Earth's mass is
, and we see that this value is slightly larger than the accepted value of
.
The Big Bang theory is matter and energy in the universe exploded out from one point. As the explosion occurred, energy and matter spread outward and formed the universe. The matter from the Big Bang formed clouds of gas.
Answer:
35.7 kg
Explanation:
We are given that
Left scale reads =200N
Right scale reads=150 N
We have to find the mass in kg.
We know that
Weight of child= Sum of two scales=200+150=350 N
Acceleration due to gravity=
We know that
Weight= mg
Using the formula


Hence, the mass of child=35.7 kg