Question

14. An object with mass 5 kg is acted upon by a force, F = (-3î + 4Î) N. If its initial velocity at t= 0 is ✓ = (6î - 12h) ms-1 the time at which it will just have a velocity along y-axis is (A) 5s (Byros C) 2s (D) 15 s​

Answer 1

Answer:

Our interest is in finding the moment when the velocity along X-axis becomes zero. So noting the initial velocity along X-axis as u=6m/s

Acceleration along X-axis is Force along X-axis/mass=−3/5=−0.6m/s

2

Time taken in making the velocity along X-axis to zero is change in velocity/acceleration=

(−0.6)

(0−6)

=10second