Q.

A body of mass 2 kg moving with velocity of v→in=3i^+4j^ ms–1 enters in to a constant force field of 6 N directed along positive z-axis. If the body remains in the field for a period of 53 seconds, then velocity of the body when it emerges from force field is         [2025]

1 4i^+3j^+5k^  
2 3i^+4j^+5k^  
3 3i^+4j^–5k^  
4 3i^+4j^+5k^  

Ans.

(2)

a→=62(k^)ms–2=3(k^)ms–2, t=53s

u→=(3i^+4j^)ms–1

v→=u→+at→=(3i^+4j^+5k^)ms–1