MENU
Question -

A body of mass 0.40 kg moving initially witha constant speed of 10 m s–1 to the north is subject to aconstant force of 8.0 N directed towards the south for 30 s. Take the instantthe force is applied to be t = 0, the position of the body atthat time to be x = 0, and predict its position at t =–5 s, 25 s, 100 s.



Answer -

Mass of the body, m = 0.40kg

Initial speed of the body, u =10 m/s due north

Force acting on the body, F =–8.0 N

Accelerationproduced in the body, 

(i) At t = –5 s

Acceleration, a‘ = 0 and u =10 m/s

=10 × (–5) = –50 m

(ii) At t = 25 s

Acceleration, a” = –20 m/s2 and u =10 m/s

(iii) At t = 100 s

For

a = –20 m/s2

u = 10 m/s

=–8700 m

For

As per the first equation of motion,for t = 30 s, final velocity is given as:

v = u + at

=10 + (–20) × 30 = –590 m/s

Velocityof the body after 30 s = –590 m/s

Formotion between 30 s to 100 s, i.e., in 70 s:

=–590 × 70 = –41300 m

∴Total distance, =–50000 m


Comment(S)

Show all Coment

Leave a Comment

Free - Previous Years Question Papers
Any questions? Ask us!
NodeJS Interview Questions Answers
ASP.Net Interview Questions Answers
Interview Questions Answers
×