Cool down the Slowest
B. Seawater, because it heats up slower and gives away heat slower than sand.
Read the question wrong the first time
Answer:
v = 0
Explanation:
This problem can be solved by taking into account:
- The equation for the calculation of the period in a spring-masss system
( 1 )
- The equation for the velocity of a simple harmonic motion
( 2 )
where m is the mass of the block, k is the spring constant, A is the amplitude (in this case A = 14 cm) and v is the velocity of the block
Hence

and by reeplacing it in ( 2 ):

In this case for 0.9 s the velocity is zero, that is, the block is in a position with the max displacement from the equilibrium.
Answer: 
Explanation:
Given
Capacitance 
Resistance 
Inductance 
In LCR circuit, current is maximum at resonance frequency i.e.

Insert the values

Also, frequency is given by

