Question

two forces point in opposite directions. their magnitudes are $f_1$ and $f_2$ and their uncertainties are $delta f_1$ and $delta f_2$. to find the net force, a student must subtract the force magnitudes: $f_{net}=f_1 - f_2$. question 1 (1 point) using the addition and subtraction rule for propagation of uncertainties, select the expression for the uncertainty in the net force. form: $r = xpm y$ rule: $delta r=delta x+delta y$ a) $delta f_{net}=delta f_1-delta f_2$ b) $delta f_{net}=delta f_1+delta f_2$ c) $delta f_{net}=delta x+delta y$ d) $delta f_{net}=3$

Explanation:

Step1: Recall uncertainty - addition rule

For a quantity $r=x\pm y$, the uncertainty $\Delta r=\Delta x+\Delta y$. Here $F_{net}=F_1 - F_2$, where $x = F_1$, $y = F_2$.

Step2: Apply rule to net - force uncertainty

The uncertainty in $F_{net}$ is $\Delta F_{net}=\Delta F_1+\Delta F_2$ according to the rule.

Answer:

B. $\Delta F_{net}=\Delta F_1+\Delta F_2$