Physics
posted by Jane on .
A particle moves in a straight line so that its position (x cm) from a fixed point O at time (t seconds) is given by x= t^36t^215t5
Find the average speed of the particle in the first 7 seconds

= t^3  6t^2  15t  5.
Xo=0^3  6*0  15*0  5 = 5 cm @ t = 0.
X=7^3  6*7^2  15*7  5 = 61 cm @ 7s.
V = D/t = (XXo)/t.
V = D/t = (61(5)) / 7 = 56 / 7=8cm/s