Answer:
you want to know newtons first law here.
Explanation:
An object that is at rest stays at rest or stays in motion.
It should be C. If the object is denser than the fluid, it will sink. If it isn't, it will float
Answer:
Explanation:
When a standing wave is formed with six loops means the normal mode of the wave is n=6, the frequency of the normal mode is given by the expression:
Where 
is the length of the string and 
the velocity of propagation. Use this expression to find the value of .
The velocity of propagation is given by the expression:
Where 
is the desirable variable of the problem, the linear mass density, and 
is the tension of the cord. The tension is equal to the weight of the mass hanging from the cord:
With the value of the tension and the velocity you can find the mass density:
<span>1 cal = 4,185 J
1 kcal = 1*10^3 cal
or
=1000 cal</span>
