Refrigerator was what is commonly used today. We do dry foods and salt cure but that is not done on a daily basis
Answer: conductors are substances that allow heat or electricity to pass through . It deals with only the flow of electrons.
Eg. water, copper wire, iron rod, some ceramic materials, metallic nail.
Insulators are materials that do not allow heat or electricity to pass through.
Eg. Book, plastic, rubber, glass, paper
Explanation:
Answer: 9.9%
Explanation: efficiency = (work output /work input) × 100
Note that, 1 kilocalorie = 4184 joules, hence 22kcal = 22× 4184 = 92048 joules.
Work output = 9200 j and work input = 92048 j
Efficiency = (9200/92048) × 100 = 0.099 × 100 = 9.9%
Answer:
L = 2.8 cm
Explanation:
Period T = 4 / 12 = 1/3 s
T = 2π√(L/g)
L = (T/2π)²g
L = ((1/3)/2π)²9.8 = 0.02758... ≈ 2.8 cm
Answer:
5.2941176471 kg or 5294.1 grams
Explanation:
g.p.e= mgh
g.p.e/gh=m
180j/10×3.4= m
180/34= m
5.2941 kg= m