These are “plug-in-the-number” type activities to familiarize yon with the equations that link the concepts of physics. They are mainly one-step substitutions and are less challenging than the Problem. ? Calculate the speed (in m/s) of a skateboarder who accelerates from rest for 3 s down a ramp at an acceleration of 5 m/s2. ?

ANSWER: The acceleration of the skateboarder is a = 5 m/s . The time for which he accelerated is t = 3 s. From the equation of motion, V = u + at-------------------(1) V = 0 + 5 × 3 = 15 m/s. CONCLUSION: After 3 seconds, the speed of the skateboarder will be 15 m/s.