Amass on a spring vibrates horizontally on a smooth level surface. its equation of motion is x(t)= 8 sin (t), where t is in seconds and x in centimeters. find the velocity and acceleration of time. find the position, velocity, and acceleration of the mass at time t=2pi/3. in what direction is it moving at that time

Solution:

we have given the equation of motion is x(t)=8sint [where t in seconds and x in centimeter]

Position, velocity and acceleration are all based on the equation of motion.

The equation represents the position.  The first derivative gives the velocity and the 2nd derivative gives the acceleration.

x(t)=8sint

x'(t)=8cost

x"(t)=-8sint

now at time t=2pi/3,

position, x(t)=8sin(2pi/3)=4*squart(3)cm.

velocity, x'(t)=8cos(2pi/3)==4cm/s

acceleration, x"(t)==8sin(2pi/3)=-4cm/s^2

so at present the direction is in y-axis.

i believe the answer would be:

d. violin, clarinet, french horn, and tuba