Question

A moving company is called into a building and asked to relocate 520 bricks to a location 15 meters above the ground. If each brick is 4 kilograms, what amount of work will be needed to accomplish the task?

A. 305,760 J
B. 229,320 J
C. 203,840 J
D. 588,000 J

Answer 1

Force is defined as the energy required to do some physical action. By formula we know that Work = force x distance. Here in this case the work required to lift one brick = mgh.

Where m=mass; g=gravity and h= height;

Given

m= 4Kg;

g=9.8m/sec2;

h=15m;

work done to lift one brick = 4 Kg x 9.8m/sec2 x 15m = 588Joules.

Then work done to lift 520 bricks = 520 x 588 = 305,760joules or 305.76KJ.

Answer 2

The amount of work will be needed to accomplish the task is a) 305760  Joules  

Given data:  

Number of bricks =  520

Distance = 15 m

Mass of brick =  4kg

$Work = Force \times Height$

$Work = (mass \times gravity) \times (height)$

$Work = (520\quad bricks) \times (4 kg/brick) \times (9.8 \frac { m }{ { s }^{ 2 } }) \times (15\quad meters)$

$Work = (520 \times 4 \times 9.8 \times 15) kg\frac { m }{ { s }^{ 2 } }$

Work = 305,760  $(kg\frac { m }{ { s }^{ 2 } }) (m)$

Work = 305760  Joules