Why is the first stage of a large roller coaster usually to take the riders up a large incline assisted by a chain under the roller coaster carts?

A.) To build potential energy which will be turned into kinetic energy throughout the majority of the ride.

B.) To build elastic potential energy which will be transformed throughout the ride.

C.) To build kinetic energy since the ride is starting from rest.

D.) To build suspense, there is no scientific reason.

when a device is used in a circuit in which the voltage is 81 v, the current flowing through the device is 3 a. what is the resistance of the device?

a. 27 ω

b. 40.5 a

c. 243 ω

d. 243 a

the correct answer is a. 27

that would be because of both gravity and friction. so     c

weight of the box is given as

here this is placed on the inclined of angle 42 degree

now this weight will have two components one is along the incline other is perpendicular to it

so here we need to apply a force parallel to incline opposite to its component of weight

so here the component of weight is given as

here we have

so it requires 75 n force to move it upwards

365.25 earth days are in the year of a light year