<span>c. run towards a source of water to extinguish the fire
</span>
Answer:
2000 nickels
Explanation:
One way to solve proportionality problems, direct and inverse: the simple 3 rule.
If the relationship between the magnitudes is direct (when one magnitude increases so does the other), the simple direct rule of three must be applied.
On the contrary, if the relationship between the magnitudes is inverse (when one magnitude increases the other decreases) the rule of three simple inverse applies.
The simple 3 rule is an operation that helps us quickly solve proportionality problems, both direct and inverse.
To make a simple rule of three we need 3 data: two magnitudes proportional to each other, and a third magnitude. From these, we will find out the fourth term of proportionality.
In the simple three rule, therefore, the proportionality relationship between two known values A and B is established, and knowing a third value C, a fourth value D is calculated.
A -> B
C -> D
Calculation
1 nickel --> 5 g
X? nickel --> 10000g
X = (10000 g * 1 nickel) / 5 g
X = 2000 nickels
Answer:
1.045 m from 120 kg
Explanation:
m1 = 120 kg
m2 = 420 kg
m = 51 kg
d = 3 m
Let m is placed at a distance y from 120 kg so that the net force on 51 kg is zero.
By use of the gravitational force
Force on m due to m1 is equal to the force on m due to m2.
![\frac{Gm_{1}m}{y^{2}}=\frac{Gm_{2}m}{\left ( d-y \right )^{2}}](https://tex.z-dn.net/?f=%5Cfrac%7BGm_%7B1%7Dm%7D%7By%5E%7B2%7D%7D%3D%5Cfrac%7BGm_%7B2%7Dm%7D%7B%5Cleft%20%28%20d-y%20%5Cright%20%29%5E%7B2%7D%7D)
![\frac{m_{1}}{y^{2}}=\frac{m_{2}}{\left ( d-y \right )^{2}}](https://tex.z-dn.net/?f=%5Cfrac%7Bm_%7B1%7D%7D%7By%5E%7B2%7D%7D%3D%5Cfrac%7Bm_%7B2%7D%7D%7B%5Cleft%20%28%20d-y%20%5Cright%20%29%5E%7B2%7D%7D)
![\frac{3-y}{y}=\sqrt{\frac{7}{2}}](https://tex.z-dn.net/?f=%5Cfrac%7B3-y%7D%7By%7D%3D%5Csqrt%7B%5Cfrac%7B7%7D%7B2%7D%7D)
3 - y = 1.87 y
3 = 2.87 y
y = 1.045 m
Thus, the net force on 51 kg is zero if it is placed at a distance of 1.045 m from 120 kg.