Suppose that with a pulley system, you need to exert a force of 1,400 N to lift a heavy object. But without the pulley system, you need to exert 4,200 N to lift the object. What is the mechanical advantage of the pulley system

3

Explanation:

Mechanical Advantage: This can be defined as the ratio of the load to the effort of a machine. Mechanical advantage has no unit because it is a ratio of two quantity of the same unit.

It can be expressed as

M.A = L/E Equation 1

M.A = Mechanical advantage, L = Load, E = Effort.

Given: L = 4200 N, E = 1400 N

Substitute into equation 1

M.A = 4200/1400

M.A = 3

Hence the mechanical advantage of the pulley system = 3

mistakes are ok

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.