Question

The displacement of a particle in x direction is given by x = 9 – 5t + 4t². Find the Velocity at time t = 0 

(A) – 8 ms^–1 

(B) – 5 ms^–1 

(C) 3 ms^–1 

(D) 10 ms^–1

Answer 1

Correct option: (B) – 5 ms^–1

Explanation:

x = 9 – 5t + 4t² 

v = (dx / dt) = – 5 + 8t 

v at t = 0 is v = – 5 m/s