What is the mass of an object travelling at 15 m/s with a kinetic energy of 100 J?
Kinetic Energy (Ek) = 1/2(mv2).This can be rearranged such that, m = (2Ek)/v2we know from the question that Ek = 100 J and we know that v = 15 m/sso plugging in the numbers, we get m = (2 x 100)/(15)2 = 200/225 = 0.89 Kg (to 3 significant figures)
TD
Related Physics GCSE answers
All answers ▸When a toothbrush is charging, p.d. across the primary coil is 230 V, p.d. across the secondary coil is 7.2 V. The primary coil in the charging base has 575 turns of wire on its coil. Find the number of turns on the secondary coil inside the toothbrush.
State Newton's 3 Laws in words and/or mathematically
If a car has a mass of 670kg and has a driving force of 1200N and a force from resistance of 300N, what is the acceleration of the car? What is the speed of the car after 5 seconds?
Two cars are crash tested. Car A has a crumple zone, B doesn't. Both cars have mass 1500kg and a driver of mass 80kg and crash at 20m/s. Cars A and B take 0.8 and 0.2 seconds to stop respectively. Using this information, are crumple zones a necessity? (6)