Fizik a 7 s I n f quvvat n: 44 Masala yechish Darsning maqsadi

Quvvat, kuch va tezlik orasidagi munoabat

• A=F s
• S= t
• A=F t
• N=

•  

N=

 

Masala yechish namunasi

Berilgan: m1=10t=10000kg m2=2t=2000 kg h =30m=0,m t=1 min=60 s g=10 m/s2	Formula: A1=m1gh A2= m2gh N1=A1/t N2=A2/t	Yechish: A1 =(10000*10*30)J=3000000J; A2= (2000*10*30) J=600000J; N1=(3000000/60)W=50000W=50kW N2 =(600000/60)W=10000W=10kW Javob: N1=50kW; N2 =10kW
N1=? N2=?

Yangi mavzuni mustahkamlash (20 daqiqa)

Ish	quvvat	vaqt
100	20
	50	10
200		4

Masala

“Nyuton” guruhiga

• Massasi 4kg bo’lgan jism kuch ta’sirida gorizontal sirtda 5s davomida 15 m masofaga tekis harakatlantirilib borildi. Sirpanuvchi sirtlarning ishqalanish koeffitsiyenti 0,2 ga teng bo’lsa, jism harakatlantirilgandagi quvvatning foydali qismini toping.

“Beruniy” guruhiga

• Ot massasi 1t bo’lgan aravani 1km masofaga 10 minutda olib bordi. Agar aravaning harakatiga qarshilik koeffitsienti 0,06 ga teng bo’lsa, ot quvvatining foydali qismini toping.

“Joul” guruhiga

• Gorizontal sirtda jism 100 N kuch ta’sirida tekis harakatlanmoqda. Tashqi kuch ta’siri to’xtaganidan keyin jism 2m masofaga sirpanib borib to’xtadi. Ishqalanish kuchining ishini toping.

§ 44 M – 30 (1-4),

§ 44 M – 30 (1-4),

Savol javob : 1-5

Uyga vazifa