In a college homecoming competition, eighteen students lift a sports car. while holding the car off the ground, each student exerts an upward force of 400 n. (a) what is the mass of the car in kilograms? (b) what is its weight in pounds?

Explanation:

Given

Each student exert a force of

Let mass of car be m

there are 18 students who lifts the car

Total force by 18 students

therefore weight of car

mass of car

(b)

note: the given question is incomplete.

complete question is given below.

which is an example of kinetic energy?

a. the energy stored in ethanol  

b. a hockey puck sliding across the ice  

c. a compressed spring  

d. a ball sitting at the top of a ramp

solution: the kinetic energy is the energy posses by the virtue of the motion of the object.

in the given options, a, c and d are the example of potential energy because it is the energy posses by the virtue of the rest of the object. but option b has the kinetic energy as the object is in motion.

hence, a hockey puck sliding across the ice   is the apex example of kinetic energy.

so, the option (b) a hockey puck sliding across the ice   is the correct option.