Question

Q43: A girl of mass 50 kg, runs up a flight of 40 stairs, each measuring 20
cm, in 50 seconds. Calculate the power of the girl.

ANSWER FAST​

Answer 1

Explanation,

Given,

• Mass (m) of a girl is 50 kg.
• Total Height (h) gained = 40 × 20 cm = 800 cm.
• Time taken (t) = 50 s
• Acceleration due to gravity (g) = 10 m/s²

To Find,

• The power of a girl.

Solution,

Firstly, convert cm into m.

⟹ Height (h) = 800 cm

⟹ h = 800/100

⟹ h = 8 m

We know that,

P = W/t

⟹ P = mgh/t

[ Put the values ]

⟹ P = 50 × 10 × 8 / 50

⟹ P = 500 × 8 / 50

⟹ P = 4000/50

⟹ P = 80 watt

Therefore,

The power of a girl is 80 watts.

Answer 2

$\huge\mathcal\colorbox{blue}{{\color{white}{★ANSWER★}}}$

$\huge\color{blue}{\textbf{\textsf{GIVEN :-}}}$

• Mass (m) of a girl = 50 kg
• Total height (h) = 40 × 20 cm = 800 cm
• Time (t) = 50 s
• Acceleration due to gravity (g) = 10 m/s²

$\huge\color{blue}{\textbf{\textsf{TO FIND :-}}}$

• The power of the girl.

$\huge\color{blue}{\textbf{\textsf{SOLUTION :-}}}$

Converting units,

Height (h) = 800 cm

→ h = 800/100

→ h = 8 m

We know that,

P = W/t

→ P = mgh/t

→ P = 50 × 10 × 8/50

→ P = 500 × 8/50

→ P = 4000/50

→ P = 80 W

Hence, the power of the girl is 80 W.

Hope it Helps Buddy ♥️