A mass of 2.8 kg is connected to a horizontal spring whose stiffness is 6.5 N/m. When the spring is relaxed, x = 0. The spring is stretched so that the initial value of x = +0.14 m. The mass is released from rest at time t = 0.
Remember that when the argument of a trigonometric function is in radians, on a calculator you have to switch the calculator to radians or convert the radians to degrees. Predict the position x when t = 1.44 s:

Position of x at t = 1.44s is - 0.0817 m

Explanation:

For the harmonic motion of the spring, the displacement is given by

x = A cos wt

A is the amplitude of displacement = 0.14 m

t = time = 1.44 s

w = angular frequency and for a spring's motion, it is given by

w = √(k/m)

k = spring's stiffness = 6.5 N/m

m = 2.8 kg

w = √(6.5/2.8) = 1.524 rad/s

x = 0.14 cos (1.524 × 1.44) = 0.14 cos 2.194 = 0.14 × - 0.5836 = - 0.0817 m

Kinetic energy of the vehicle is

Explanation:

Kinetic Energy of the vehicle is given as

now we have

m = 1860 kg

now we have