Question
(a) A car accelerates at a constant rate of 1.83m/s^2 along a flat straight road. The force acting on the car is 1.870 kN. Calculate the mass of the car. Give your answer to three significant figures. (3) __ (b) The car accelerates from rest for 16 s. Calculate the speed of the car after 16 s. speed=
Answer
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Kade
Master · Tutor for 5 years
Answer
【Explanation】: This question involves the Physics principles of force, acceleration and motion.(a) From the definition of force, Force = mass * acceleration (This is Newton's Second Law of Motion). In this case, we know the force and the acceleration and we need to find the mass. So, we can rearrange the formula to be mass = Force / acceleration. Since the force is given is kN (kilo Newtons), we need to convert it to Newtons (1 kN = 1000 N). (b) From the definition of acceleration, it is the change in speed over time. Thus, the speed after t seconds of constant acceleration a from rest (initial speed = 0) is given by Speed = acceleration * time.【Answer】: 4 (a) Answer: mass = 1023 kg4 (b) Answer: speed = 29.3 m/s