Who is good at physics?

Who's good at physics?? i need helpp?

• i never liked physics, but i need someone who enjoys physics and is good at it i have some questions if you can answer them i will respect you. here are the questions, i will give the information to help you. THANKS YOU :) the motors of a roller coaster take 30 second to move the cars and riders to the top of the track. there are two motors, the voltage is 415V and the current through each motor is 40A Assume that the acceleration of free-fall due to gravity is 10m/s squared. show all your working for your answers. 1) the volocity of the cars at the bottom of the first drop is 27m/s, and the mass of cars and riders is 2490kg. a. what is the kinetic energy of the cars and riders at the bottom of the first drop? 2)how much potential energy will the cars and occupants gain at the top of the loop? 3) at the end of the ride, the cars and occupants stop until the next cars have moved up the track. the motors apply a force of 1750 N and move the cars and occupants 45m. how much do the motors do? thankyou soo much, for your time !! i reallly appriciate it

• Answer:

  1) KE = 1/2 m v^2 =.5*2490*27^2 = 9.07x 10^5 Joules 2) Energy is conserved. The PE at the top is equal to the KE energy at the bottom. TE = KE + PE. at the top KE = 0 at the bottom PE = 0. PE at the top is 9.07x 10^5 Joules. The same as KE at the bottom. 3) I think 3 is asking for the amount of work.. maybe you left out that word. W = Fd = 1750*45 = 7.88 x 10^4 Nm