Answer:
Explanation:
velocity is the change in displacement of a body with respect to time. Given the displacement d (m) of a block sliding along a straight line is given by the equation d = -0.65 t + 0.21 t², where t is the time in seconds, instantaneous velocity is expressed by differentiating the displacement with respect to time
Velocity = dd/dt
Velocity = -0.65 + 2(0.21)t²⁻¹
Velocity = -0.65 + 0.42t
The instantaneous velocity of the block when t = 2.0 s can be gotten by substituting t = 2.0s into the expression above:
Velocity = -0.65 + 0.42(2)
Velocity = -0.65 + 0.84
Velocity = 0.19
Hence the instantaneous velocity of the block when t = 2.0 s is 0.19m/s
