Answer:
b. varies inversely with the square of the distance from the center of Earth.
Explanation:
Comparing the Newton's law of universal gravitation and second law of motion;
from Newton's second law of motion,
F = ma ............. 1
from New ton's law of universal gravitation,
F = ........... 2
Equating 1 and 2, we have;
mg =
g =
Therefore, the acceleration due to gravity near Earth, g, is inversely proportional to the square of the distance from the center of Earth.
The block moves with constant velocity: for Newton's second law, this means that the resultant of the forces acting on the block is zero, because the acceleration is zero.
We are only concerned about the horizontal direction, and there are only two forces acting along this direction: the force F pushing the block and the frictional force
acting against the motion. Since their resultant must be zero, we have:
The frictional force is
where
is the coefficient of kinetic friction
is the weight of the block.
Substituting these values, we find the magnitude of the force F:
Answer:
DETAILS IN THE QUESTION INSUFFICIENT TO ANSWER
Explanation:
Assuming the liquid to be water ,
the density of water is :
Buoyant force exerted by a liquid on an object with of it's volume immersed is :
where ,
- is the buoyant force
- is the density of the liquid
- is the acceleration due to gravity
Thus at equilibrium:
from these , we get the density of brass to be
which is not possible
It must be sliding friction, because the fish is already in motion.