Rose Harrison, Clara Huizink, Aidan Sproat Clements and, Marlene Torres Skoumal Solutions for Exercise 16: Review in context

Three resistors, $A, B \text{and} C$, are connected in parallel. Resistor $A$ has resistance $r$ ohms. Resistor $B\text{'}s$ resistance is $4$ ohms larger than resistor $A\text{'}s$. Resistor $C$, the largest, has a resistance two ohms more than twice that of resistor $A$. Write down an expression for the total resistance of the circuit. Simplify the expression into a single fraction

Three resistors, $A, B \text{and} C$, are connected in parallel. Resistor A has resistance $r$ ohms. Resistor $B\text{'}s$ resistance is $4$ ohms larger than resistor $A\text{'}s$. Resistor $C$, the largest, has a resistance two ohms more than twice that of resistor $A$. Write down an expression for the total resistance of the circuit. Simplify the expression into a single fraction. A fourth resistor, $D$, has the same resistance as resistor $C$. It is connected in series with resistors $A, B, \text{and} C$. Write down an expression for the total resistance of the circuit. Simplify the expression into a single fraction.

Ohm's Law states that the voltage $\left(V\right)$, in an electrical circuit with current $\left(I\right)$ and total resistance, $R$, is given by $V=IR$. Make $I$ as the subject of the formula.

Ohm's Law states that the voltage $\left(V\right)$, in an electrical circuit with current $\left(I\right)$ and total resistance, $R$, is given by $V=IR$. Make $I$ as the subject of the formula.

Circuit $A$ has a resistor of $6$ ohms and a second resistor with resistance $r$, connected in series. Circuit $B$ has a resistor of $5$ ohms and a second resistor with resistance $3r$. Circuit $A$ and circuit $B$ are connected in parallel. The voltage in the complete circuit is $12$ volts. Find the total resistance of the circuit and hence find an expression for the total current flowing through the complete circuit in terms of $r$.

Determine how many times larger the force of gravity is when the distance between the two masses is halved.

One mass is doubled and the distance between the masses is increased by scale factor $4$. Determine the effect on the gravitational force between them

One mass is doubled, the other is tripled and the distance between them is reduced by scale factor $4$. Determine the effect on the gravitational force between them.

One mass is halved and the other is made eight times larger. Find how the distance $r$ needs to change to keep the gravitational force the same.