Given F=(4t3i^−3tj^) N, m = 4 kg
a=mF=t3i^−43tj^
Integrating with v(0)=0:
v=4t4i^−83t2j^
At t=2: v=416i^−812j^=4i^−23j^
Integrating with r(0)=0:
r=20t5i^−8t3j^
At t=2: r=2032i^−88j^=58i^−j^
JEE Main 2026 — Physics Mechanics
A 4 kg mass moves under the influence of a force F=(4t3i^−3tj^)N where t is the time in second. If mass starts from origin at t=0, the velocity and position after t=2 s will be:
Held on 21 Jan 2026 · Verified 6 Jul 2026.
v=4i^−23j^r=56i^−j^
v=3i^+23j^r=56i^+j^
v=4i^−23j^r=58i^−j^
v=4i^+25j^r=58i^+2j^
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