$(a)$ When a motorcar makes a sharp turn at a high speed,we tend to get thrown to one side. Why?
$(b)$ State Newton's first and third law of motion.
$(c)$ $A$ force of $5 \ N$ gives a body of mass $m$ an acceleration of $10 \ m \ s^{-2}$. Calculate the mass of the body in grams.

(C) This happens due to the inertia of direction. According to Newton's first law,an object continues to move in its original direction unless an external force acts on it. When the car turns,our body tends to maintain its original straight-line path,causing us to lean to the side.
$(b)$ Newton's first law of motion states that an object remains in a state of rest or uniform motion in a straight line unless compelled to change that state by an applied external force. Newton's third law of motion states that to every action,there is always an equal and opposite reaction.
$(c)$ Given: Force $F = 5 \ N$,acceleration $a = 10 \ m \ s^{-2}$.
Using Newton's second law,$F = m \times a$,so $m = F / a$.
$m = 5 \ N / 10 \ m \ s^{-2} = 0.5 \ kg$.
Since $1 \ kg = 1000 \ g$,the mass is $0.5 \times 1000 = 500 \ g$.