Someone please help
Just need answers
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Answer:
As follows,
Explanation:
KE=1/2mv^2
In 1st question,
KE=1/2mv^2=1/2*0.05*12=0.3 J [50g=0.05 kg]
In 2nd question,
KE=1/2mv^2
6.8=1/2*0.046*v^2
v=sqrt(6.8/0.023)
v=17.19
In 3rd question,
KE=1/2mv^2
63/392=m
m=0.16kg=160g
For 4th,
a.
1st case,
KE=1/2mv^2=1/2*28*2.4^2=80.64
2nd case,
KE=1/2mv^2=1/2*28*3.7^2=191.66
Change in KE=191.66-80.64=11.02
b.Speed/velocity gained