A roller coaster consists of carts has a mass of 200 kg. A - What is the velocity of the cart at the bottom of the roller coaster if it has a kinetic energy of 160 000J?

B - If 20% of the energy was wasted as heat and sound when the cart rolled down the roller coaster, what was the total gravitational potential energy that the roller coaster started with (g=9.81 N/kg)?

C - What was the height at the top of the roller coaster?

D - If the roller coaster cart gained this gravitational potential energy through a pulley system with a motor, and the motor took 30 seconds to pull the cart from the bottom to the top what was the power of the motor?

b.transmitters send radio waves, and receivers capture radio waves.

i had this question and the answer was 3.15 miles.

martina travels from school to her mom's office. from there, she walks to school. after school, she walks to the library and then to a friends house before finally ending back at home. find martina's total distance traveled.

a) 0 miles  

b) 0.4 miles  

c) 1 mile  

d) 3.15 miles

energy stored in the capacitor= 9.72 x 10⁻⁴ j

explanation:

the energy stored in the capacitor is given by

e= 1/2 c v²

e= energy stored

c= capacitance= 1.5 µc= 1.5 x 10⁻⁶f

v= potential difference=36 v

so energy stored= e= 1/2 (1.5 x 10⁻⁶) (36)²

energy stored= 9.72 x 10⁻⁴j