A 90.5kg man standing on a surface of negligible friction kicks forward a 45gm stone lying at his feet so that it acquires a speed of 3.05m/s. what velocity does the main acquire as a result?

0.0015

Explanation:

Given parameters:

Mass of man = 90.5kg

Mass of stone = 45g

Speed of stone  = 3.05m/s

Unknown:

Velocity of man  = ?

Solution:

What relates the man to the stone is the momentum. The momentum lost by man in kicking the stone is gained by the moving stone. This way momentum is conserved.

Momentum  = mass x velocity

         Momentum lost by man = momentum gained by stone

              M₁V₁  = M₂V₂

1 denotes man

2 denotes stone

            since V₁ is unknown, we make it the subject in the expression.

   convert mass to kg;

           45g  =  0.045kg

       V₁   =    =  

    V₁   = 0.0015m/s

glacial erosion, the picking up and movement of earth beneath a glacier, is also referred to as plucking. erosion and transportation of individual pieces of bedrock, especially large "joint block occur as a result of this glacial erosion. plucking is type of erosion in which rocks become frozen into the bottom and sides of the glacier.as the glacier moves downhill it 'plucks' the rocks frozen into the glacier from the ground.

the energy generated by an individual's metabolism is calculated in met (metabolic equivalent of task). the met is the ratio of the work metabolic rate to the resting metabolic rate. one met is illustrated as 1 kcal per kilogram per hour, and is probably equal to the energy cost of sitting quietly.

1 met is equal to 1.162 watt per kg

1 kg is equal to 1000 grams

as the person weighs 80000 gm, that is, 80 kg.

therefore, 80*1.162 = 92.96

thus, the person expends 92.96 watts of power while at rest.