Its B: reduce the amount of energy needed to do the work by putting the work onto something else
Density is a property of the substance, and doesn't depend on
how much of it you have.
One drop of the shampoo and a supertanker-full of the same
shampoo have the same density.
Answer:
It decreases by a factor of 4
Explanation:
The gravitational force between two masses is given by
where
G is the gravitational constant
m1, m2 are the two masses
r is the separation between the two masses
In this problem, the distance between the masses is doubled, so
r' = 2r
Substituting into the equation, we see that the new force is
So, the force decreases by a factor of 4.
Answer:
A volcano that erupts frequently.
Explanation:
Both.
But the volcano that hasn't erupted in 100 years would probably be more dangerous because you wouldn't be prepared for its explosion as you would be for the one that erupts frequently.
Glad I could help!!
Answer:
The correct answer is D. Static friction is much stronger than kinetic friction, so it takes more force to get an object moving than it does to keep it moving.
Explanation:
We can eliminate choice A if we know that both static friction and kinetic friction depend on what are called the coefficients of static friction and kinetic friction, respectively. These coefficients are a reflection of the nature of the surface. In other words, both static friction and kinetic friction depend on the surface material (choice A is incorrect).
Choice B is incorrect because static friction applies to still (static) object whereas kinetic friction applies to moving objects (that have kinetic energy).
Choice C is also incorrect.
Choice D is correct as described in the given information. It takes much more force to start an object from rest than to keep it moving. Think about things in your everyday life - it takes a push to get a toy car moving along the ground, but you do not need to consistently push the car with the same force to keep it moving. This reflects that static friction is much stronger than kinetic friction, which is also described by the relationship between their coefficients (the coefficient of static friction is generally greater than that of kinetic friction).
Hope this helps!
