Aperson pushes a box up a ramp that is 3m long and 1 m high if the box has a mass of 20 kg and the person pushes with a force of 80 n what is the efficiency of the ramp

The efficiency of the ramp11%

Explanation:

Let AC be the length of inclined plane or ramp = 3m (given)

BC be the height through which the load is lifted = 1m.

Load or Box (L) = 20kg  

= 20×9.8 N = 196N

Effort (E) =  

= 196 ×0.33 =64.68

where θ is the angle between AC and AB.

Therefore,

Mechanical Advantage (MA) =  

MA = 0.33.

Now, Velocity Ratio (VR) =

=  

= 3/1 = 3  

Efficiency =

=  

=0.11 = 11% which is the efficiency of the ramp

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.