Paper 5 October/November 2010 MATHEMATICS (9709/53) A Levels
لطفا برای اطمینان از عملکرد و تجربه بهتر از مرورگرهای مدرن و به روز مانند کروم یا فایرفاکس استفاده کنید.

A car of mass $700{\text{ }}kg$ is travelling along a straight horizontal road. The resistance to motion is constant and equal to $600{\text{ }}N$.
a) Find the driving force of the car’s engine at an instant when the acceleration is $2{\text{ }}m{\text{ }}{s^{ - 2}}$.
b) Given that the car’s speed at this instant is $15{\text{ }}m{\text{ }}{s^{ - 1}}$, find the rate at which the car’s engine is working.