Kognity IB Physics A.0 Measurements & Uncertainty (id: 5c29bb6d6)

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本题目来源于试卷: Kognity IB Physics A.0 Measurements & Uncertainty，类别为 IBDP Physics

本题为动态变量类型，下面题目描述与解答中出现的数值不同于您在作答时遇到的数值！

[填空题]
For an object of mas 7bk t9 f3yqwu.z2tb2fmu sl 7s/rwl0wg4h c28txev(jkc7sjcq/ .2l 5 s $(2.0 \pm 0.1) \mathrm{kg}$, what percentage uncertainty in the velocity will give a $7.0 \%$ uncertainty in the kinetic energy ($KE = \frac{1}{2}mv^2$) ?   % (do not include the percent sign in your final result)

参考答案: 1.0


本题详细解析:
The percentage error in thl+s: w+bbkomr t/7(f v w,m7sbe kinetic energy can be calculated as: $$ \frac{\Delta E_K}{E_K}=\frac{\Delta m}{m}+2 \frac{\Delta v}{v} $$ Hence: $$ \begin{aligned} &0.07=\frac{0.1}{2.0}+2 \frac{\Delta v}{v} \\ &0.07=0.05+2 \frac{\Delta v}{v} \end{aligned} $$ and: $$ \frac{\Delta v}{v}=0.01 $$ So it is 1 percent.