Question

1. determine the centripetal force on a 250 g rock in a slingshot with a tangential velocity of 7.6 m/s. the string for the slingshot is 0.45 meter long.

4.2 n
32,000 n
32 n
4,200 n

Explanation:

Step1: Convert mass to SI unit

First, convert the mass of the rock from grams to kilograms. Given $m = 250\ g=0.25\ kg$, $v = 7.6\ m/s$ and $r=0.45\ m$.

Step2: Apply centripetal - force formula

The formula for centripetal force is $F_c=\frac{mv^{2}}{r}$. Substitute the values: $F_c=\frac{0.25\times(7.6)^{2}}{0.45}$.
Calculate $(7.6)^{2}=57.76$. Then $0.25\times57.76 = 14.44$.
Now, $F_c=\frac{14.44}{0.45}\approx32\ N$.

Answer:

32 N