)what is the average useful power output of a person who does 6.00×106 j of useful work in 8.00 h? (b) working at this rate, how long will it take this person to lift 2000 kg of bricks 1.50 m to a platform? (work done to lift his body can be omitted because it is not considered useful output here.)

a) The average useful power output of a person is 208.3 W

b) It take 141.14 s for this person to lift 2000 kg of bricks 1.50 m to a platform

Explanation:

a) We know that,

Where ,

P is the power consumed  

W is the work done

t is the time elapsed

Given: t = 8 hr and  

Substituting known information in the power equation, we get

Convert hr into sec,

So,

b) Given:

m = 2000 kg

h = 1.50 m

we know,

The formula for potential energy depends on the force acting on the two objects. For the gravitational force the formula is , where m is the mass in kilograms, g is the acceleration due to gravity (at the surface of the earth) and h is the height in meters.

Put this in power equation, we get

From above, find time by substituting the known values, we get

answer:   you might love summer weather, but you don’t want it to feel like the sun is inside your car. but a hot car that just won’t seem to cool down might be a bigger of a problem than you think. your car relies on being at the right temperature.

explanation:

volts times amps 6 x 0.5 3w