(C)
...........................
The correct formula for
this simple harmonic motion is:
x = (6.0) cos [ (3 pi) t +
pi/3 ]
A. Calculating for displacement
x at t = 2:
x =6.0 cos (19/3 pi)
x = 6 (0.5)
x = 3 m
<span>B. Velocity is equivalent
to the 1st derivative of the equation. v = dx / dt </span>
<span> Velocity v = dx/dt = -18 pi sin (3pi t + pi/3) </span>
v = - 18 pi sin (6pi +
pi/3)
v = 49.0 m/s
<span>C. Acceleration is the 2nd
derivative or the 1st derivative of velocity dv / dt</span>
Acceleration a = dv/dt = -54 pi^2 cos(3pi t + pi/3)
a = -54 pi^2 cos(3pi * 2 +
pi/3)
a = 386.34 m/s^2
D. Phase = pi/3
E. frequency f= 3pi/2pi =
1.5Hz
<span>F. period = 1/f = 1/1.5 = .6667sec </span>
Answer:
Specific heat of liquid 
Explanation:
We know in thermal equilibrium :
Loss in heat by iron block = Gain in heat by liquid .
Specific heat of iron = 0.45 
{ source internet }
Now , loss in heat by iron block = 
Heat gain by liquid=
Equating both we get :
D. All of these, they’re all part of scientific inquiry
