Question
Physics Question on work
The particle of mass 50kg is at rest. The work done to accelerates it by 20m/s in 10s is
A
103J
B
104J
C
2×103J
D
4×104J
Answer
104J
Explanation
Solution
v=u+at 20=0+a×10 20=a×10 a=2m/s2 Then, s=ut+21at2 s=0+21×2×10×10 s=100m Work done W=F×s or or W=ma×s ∴W=50×2×100 W=10000=104J