Civil Engineering - Applied Mechanics - Discussion

Discussion Forum : Applied Mechanics - Section 1 (Q.No. 4)
4.
The equation of motion of a particle starting from rest along a straight line is x = t3 - 3t2 + 5. The ratio of the accelerations after 5 sec and 3 sec will be
2
3
4
5
Answer: Option
Explanation:
No answer description is available. Let's discuss.
Discussion:
14 comments Page 2 of 2.

SEKHAR ALVAKONDA said:   7 years ago
Thank you all.
(1)

Sheraz said:   4 years ago
Thanks for explaining.

Lebohang said:   3 years ago
Really helpful, thanks all.

Suman ghimire said:   3 years ago
Equation of motion x = t^3-3t^2+5.

The equation to calculate the distance (in question it is given that the particle is moving along a straight line).

Differentiate with time to get velocity:

v = dx/dt = 3t^2-6t --> Velocity.
a = d^2x/dt = 6t-6 --> Acceleration.

Hence, when t = 5 sec.
a = 6*5 - 6 = 24.

When t = 3sec.

a = 6*3 - 6 = 12.
Ratio = 24/2 = 2.
(14)


Post your comments here:

Your comments will be displayed after verification.