Question

Position of particle located on x-axis changes with time (t) as x = 2.5t2.
Speed of the particle at t = 5 seconds is equal to?

• A. 5 m/s
• B. 10 m/s
• C. 25 m/s
• D. 50 m/s

Answer 1

The Correct Option is A

We can find the velocity (v) of the particle at any time by taking the derivative of its position (x) with respect to time (t):v = dx/dt
For the given position function, x = 2.5t^2, we have:
v = d(2.5t^2)/dt = 5t
Therefore, the velocity of the particle at time t is 5t m/s.
To find the velocity at t = 5 seconds, we substitute t = 5 into the expression for v:
v = 5t = 5(5) = 25 m/s
Hence, the speed of the particle at t = 5 seconds is 25 m/s. Note that speed is the magnitude of velocity and is always non-negative, so we don't need to include a sign.
The correct Answer is C.