Question

a girl carries a 10 kg bags upstairs to a height of 18 steps each 20cm high calculate the amount of work
​

Answer 1

Answer:

work = 3600 joules

Explanation:

work = force x displacement

= 10 x 18 x 20

= 3600

Answer 2

Given :-

Mass of the bag = 10 kg

Number of steps = 18 steps

Height of each step = 20 cm

To Find :-

The work done by the girl.

Analysis :-

Here we are given with the mass, number of steps and height of each step.

Firstly, find the total height of the staircase by multiplying the number of steps and the height of each step.

In order to find the work done substitute the given values from the questions accordingly such that work done is equal to mass into gravity into height.

Solution :-

Total height,

Total height of the staircase = No. of steps × Height of each step

Substituting their values,

⇒ 18 × 20

⇒ 360 cm

Using the formula,

$\underline{\boxed{\sf Work \ done=Mass \times Gravity \times Height}}$

We know that,

• m = Mass
• w = Work done
• g = Gravity
• h = Height

Given that,

Mass (m) = 10 kg

Gravity (g) = 10 m/s

Height (h) = 360 cm = 3.6 m

Substituting their values,

⇒ w = mgh

⇒ w = 10 × 10 × 3.6

⇒ w = 100 × 3.6

⇒ w = 360 J

Therefore, the work done by the girl is 360 J.