Answer:
option c. 21.0
Explanation:
It was given that to find 3 significant figures. So the answer is 21.0
Answer:
A lever is a rigid bar which moves freely about a fixed point called fulcrum.
Answer: B.)He should wire each room in parallel with the next
Explanation:
The voltage across each component connected in parallel is same. When a component in a parallel circuit, it does not effect working of other components. On the other hand, when a component in series circuit is switched off, whole circuit breaks and other components stop working as well. Thus, in order to create a plan that will allow the homeowners to turn off lights in one room without turning the light off the lights in another, he should wire each room in parallel with the next. Option B is correct.
If you write down the formula for friction, you will get an answer.
Ff = u * N Where N is a push down force that an object experiences.
u (mu) is a constant and has no units
It may not be accelerating and still experience friction. A is not correct.
Color and Density will not affect the frictional force. B is not so.
Buoyant forces are a different thing altogether. Generally friction has nothing to do with them. C is incorrect.
The last one is your answer. Technically mg should be the answer and not mass, but the second part is correct.
Answer:
Because on different surfaces there's more/less friction. Smooth surfaces will allow the duster to accelerate while rough surfaces will decrease the acceleration.