Answer:
2. The metal surface exerts less frictional force because there are fewer bumps and irregularities on it than there are on the concrete.
Explanation:
Frictional force is a force that is exerted between two surfaces in contact with each other. Frictional force always opposes the direction of relative motion of the two surfaces: for instance, for a ball moving along a surface, the force of friction exerted by the surface on the ball points opposite to the direction of motion of the ball.
The magnitude of the frictional force for a ball moving on a flat surface is given by
where
is the coefficient of friction
m is the mass of the ball
g is the acceleration of gravity
The value of depends on the type of surface involved. In particular, a smooth surface has a smaller value of , while a rough surface will have a bigger value. In this case, we are comparing a smooth metal surface with concrete: since the metal surface has fewer bumps and irregularities than concrete, it has a smaller value of coefficient of friction, so it exerts less frictional force than concrete.
<span>The second law of thermodynamics states that the entropy of any isolated system always increases.
So the paper tends to approach high entropy
Answer is C</span>
Answer:
Sink
Explanation:
The normal density of water is 1 g/cm3. Since the rock has a higher density of 1.72g/cm3, it will sink in water.
He would need to grow. it in sand or grit since Cactus's are usually grown in dry soil like sand.
U = 0, initial vertical velocity
v = 60 mph = 88 ft/s
Ignore air resistance and take g = 32 ft/s².
It t = time to attain 60 mph, then
(88 ft/s) = (32 ft/s²)*(t s)
t = 88/32 = 2.75 s
Answer: 2.75 s
