Question

. A rotatory comedy with power of 300 watt and period 5 minutes rotates 5 rounds. The energy it uses is​

Answer 1

Given :

• Power = 150 watt
• Period = 5 minutes
• Number of rounds = 5

To find :

• Energy used by rotary comedy

SoIution :

Here we have ;

⇔ Power (P) = 300 watt

⇔ Period = 5 minutes = (5 × 60) = 300 s

⇔ Number of rounds = 5

Now at first we have to find time :

⇔ Period = Time/Number of rounds

⇒ 300 = Time/5

⇒ Time = 300 × 5

⇒ Time (t) = 1500 s

Now we know that :

⇔ Energy = Power (P) × Time (t)

⇒ Energy = 300 × 1500

⇒ Energy = 450,000 J

⇒ Energy = 450000/1000 kJ

⇒ Energy = 450 kJ

Therefore,

Energy used by rotary comedy = 450000 J/ 450 kJ

Answer 2

Explanation:

Given that, a rotatory comedy with power of 300 watt and period 5 minutes rotates 5 rounds.

We have to find the energy used by the rotatory comedy.

Now,

Time = Period × Number of turns

Time = 300 × 5

Time = 1500 sec

Also,

Energy = Power × Time

From above data time is 1500 sec and given that power is 300 W.

So,

Energy = 300 × 1500

Energy = 450000 J

Hence, the energy used by the rotatory comedy is 45000J.

To convert J into kJ. Divide the given value by 1000.

Hence, the energy used by the rotatory comedy is 450kJ.