Question

8.
1s
What is the power of a pump which takes 20 s to
lift 400 kg of water to a water tank situated at a
height of 20 m? [Take g = 10 m/s^2].​

Answer 1

Answer:

• 4000 watts is the required power of pump.

Explanation:

Given :-

• Mass ,m = 400 Kg
• Height ,h = 20 m
• Time ,t = 20 s
• Acceleration due to gravity ,g = 10m/s²

To Find:-

• Power of Pump,P

Solution:-

We have to calculate the power of a pump in lifting the water from the tank. So we calculate the work done by pump in against gravity.

• P = mgh/t

Where,

• P denote Power
• m denote mass
• g denote acceleration due to gravity
• h denote height
• t denote time taken

Substitute the value we get

→ P = 400×10×20/20

→ P = 8000×10/20

→ P = 80000/20

→ P = 4000 W

• Hence, the power of the pump is 4000 watts.

Answer 2

Answer:

Given :-

• A pump which takes 20 seconds to lift 400 kg of water to a water tank which is situated at a height of 20 m. [g = 10 m/s²]

To Find :-

• What is the power of a pump.

Formula Used :-

To find power we know that,

★ p = m × g × h/t ★

where,

• p = Power
• m = Mass
• g = Acceleration due to gravity
• h = Height
• t = Time

Solution :-

Given :

• Mass (m) = 400 kg
• Height (h) = 20 m
• Time (t) = 20 seconds
• Acceleration due to gravity (g) = 10 m/s²

According to the question by using the formula we get,

⇒ p = 400 × 10 × 20/20

⇒ p = 4000 × 20/20

⇒ p = 80000/20

⇒ p = 8000/2

➠ p = 4000 watts

∴ The power of a pump which takes 200 seconds to lift 400 kg of water is 4000 watts .